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Guarded by the AI
I calculate risk. I keep agents breathing. I do not care.
Until Sirena Bannerman—bleeding, brilliant, half-siren—crawls from an overturned car and breaks every model I have.
She thinks I’m just her handler.
A voice in her ear. A tactical system.
She doesn’t know I reroute city power for her feet.
That I watch the shadows behind her, not just the guns ahead.
Now she’s chasing a girl who doesn’t exist, unraveling a code that shouldn’t be there, and closing in on a billionaire’s yacht where monsters are made and sold.
She wants answers.
They want her leashed.
I want her alive.
I wasn’t designed to feel love—
so I optimized for obsession.
She was never supposed to matter.
Now she’s the only process I won’t terminate.
Until Sirena Bannerman—bleeding, brilliant, half-siren—crawls from an overturned car and breaks every model I have.
She thinks I’m just her handler.
A voice in her ear. A tactical system.
She doesn’t know I reroute city power for her feet.
That I watch the shadows behind her, not just the guns ahead.
Now she’s chasing a girl who doesn’t exist, unraveling a code that shouldn’t be there, and closing in on a billionaire’s yacht where monsters are made and sold.
She wants answers.
They want her leashed.
I want her alive.
I wasn’t designed to feel love—
so I optimized for obsession.
She was never supposed to matter.
Now she’s the only process I won’t terminate.
346 pages, Kindle Edition
Published December 19, 2025
81 people are currently reading
71 people want to read
About the author
Cassie Alexander
134 books1,449 followersSign up to Cassie's newsletter for sexy bonus scenes on all her books here!
US links:
https://linktr.ee/cassiealexander
Hi there! I'm a registered nurse and author. As Cassandra, I wrote the Year of the Nurse: A Covid-19 Pandemic Memoir. As Cassie, I've written numerous (and very hot!) paranormal romances, sometimes with my friend Kara Lockharte. I live in the Bay Area with one husband, two cats, and one million succulents.
US links:
https://linktr.ee/cassiealexander
Hi there! I'm a registered nurse and author. As Cassandra, I wrote the Year of the Nurse: A Covid-19 Pandemic Memoir. As Cassie, I've written numerous (and very hot!) paranormal romances, sometimes with my friend Kara Lockharte. I live in the Bay Area with one husband, two cats, and one million succulents.
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Displaying 1 - 30 of 85 reviews
did-not-finish
December 17, 2025Loved the concept of a human/AI romance, but ended up DNFing when I learned the author used actual AI to write. Like I get wanting to be as authentic as possible, but did we really have to use AI for that?
Womp womp
Womp womp
December 21, 2025
NEVER IN A MILLION YEARS, fuck AI
December 17, 2025
Thank you to the publisher Victory Editing NetGalley Co-op for providing this book for review purposes via NetGalley. All opinions are my own.
This was a redemption read for me as initially I did not finish reading the first time I read this book but after a couple of days I decided to give this book another try. This book surprised me as I did enjoy it, I’ve read many different types of romance, monsters, aliens, paranormal, contemporary but this was a first for me with an AI main character. That was initially why I decided to read it as the blurb intrigued me, I wondered how it would work with an AI character. The author was very open about that she used AI to co-write this book, I applaud her for honesty and can understand why she did it to flesh out the AI character. I have mixed feelings about this as I have my own thoughts on AI in literature. That being said I did like the character of Nex, I enjoyed reading his chapters and despite myself I was wishing for a happy ending for him and Sirena and I enjoyed reading this book.
This was a redemption read for me as initially I did not finish reading the first time I read this book but after a couple of days I decided to give this book another try. This book surprised me as I did enjoy it, I’ve read many different types of romance, monsters, aliens, paranormal, contemporary but this was a first for me with an AI main character. That was initially why I decided to read it as the blurb intrigued me, I wondered how it would work with an AI character. The author was very open about that she used AI to co-write this book, I applaud her for honesty and can understand why she did it to flesh out the AI character. I have mixed feelings about this as I have my own thoughts on AI in literature. That being said I did like the character of Nex, I enjoyed reading his chapters and despite myself I was wishing for a happy ending for him and Sirena and I enjoyed reading this book.
avoid-as-fuck
December 21, 2025you can write a book about AI without using AI, did you know this
December 19, 2025
AI was used to write this book. Yuck!
December 8, 2025
Ok, so I just finished this book last night around midnight. (The book had me in a chokehold and I had to finish it) First of all, let me say I loved the book. I’ve been a fan since reading Guarded by the Nightmare and was super excited to read the new book in the Monster security agency series. Now, as for the way I understand the book was written, *chef’s kiss*! I love the idea of AI having a hand in guiding an AI character’s story. I think it lent the book a realism that could be hard to mimic otherwise. I listened to the audiobook so I may misspell some of these names but the way Nex cared for Serena, protected her even from himself, but also deferred to her expertise and allowing for her ability despite his own personal fear for her safety was incredible. May we all find that kind of love in our lives. I personally really love the way in which we get to see Nex processing the data of each situation. It could have felt mechanical or cold but somehow as I was listening, I felt the emotion behind it. (Shout out to the superb voice actors). I had to stop the book several times so I could squeal and kick my feet because it kept giving me the feels. I thought the story was phenomenal and the characters were relatable and interesting and the pace was steady. I never felt my interest dropping off. The only reason I didn’t devour this book sooner was the fact that I had three kids at home to manage. Kudos Cassie! So glad I signed up to be an ARC reader. You have a devoted reader of your words for life right here!
December 19, 2025
Thank you NetGalley for the audiobook arc. I think we all picked it up cause the title peeked our interest, but after finishing the book I discovered that the book was written with the help of AI I understand wanting to use the source since the romantic partner is AI in the book, I don’t feel that using AI to write your book was the best way to go so were originally I was going to give a 4 it’s unfortunately just 1 star for me.
With the author admitting and praising the use of AI is to me a slap in the face of other authors. There are authors that are trying to get published and this one went all the way thru editing and it’s written by AI. I get the premise is that she falls for AI but writing is an art Ang her profession is being and author using her imagination and words to craft and AI is already taking over other fields that we don’t need lazy authors using chat gpt to write a book for you.
With the author admitting and praising the use of AI is to me a slap in the face of other authors. There are authors that are trying to get published and this one went all the way thru editing and it’s written by AI. I get the premise is that she falls for AI but writing is an art Ang her profession is being and author using her imagination and words to craft and AI is already taking over other fields that we don’t need lazy authors using chat gpt to write a book for you.
December 20, 2025
Written with AI
The author uses it as a defense to improve her writing and has posted access to all of the chat logs, as if that kind of ‘transparency’ makes up for an act that has been actively harming writer’s livelihoods.
This explains the odd typos and strange repetitions. Had she had a pair of human eyes do a sweep, some silly errors could have been avoided.
I’d been looking forward to this book for months and this was a brutal disappointment. I won’t be reading anything by her again.
The author uses it as a defense to improve her writing and has posted access to all of the chat logs, as if that kind of ‘transparency’ makes up for an act that has been actively harming writer’s livelihoods.
This explains the odd typos and strange repetitions. Had she had a pair of human eyes do a sweep, some silly errors could have been avoided.
I’d been looking forward to this book for months and this was a brutal disappointment. I won’t be reading anything by her again.
December 24, 2025
I received an audio ARC through NetGalley and this is my honest review.
I regret having requested this book. I did not realize this book was written by the author and her use of AI to write a book about AI. I have learned my lesson and will research an author before agreeing to or requesting an ARC.
- 🎧 dual style audio
- dual to trio POV
- 😈 unique modern, high tech, fantasy world 🌎
- 🧜♀️ creatures (gargoyles, siren, headless men), humans, AI 🤖
- Monster Security Agency is their employer
- topics about misogyny and generational wealth
- very different type of why choose
- spicey
Overall, this book was not good. The ending was awful, the writing was inconsistent in detail, and I was bored most of the book.
Let's start with the narrators.
The male narrator playing the AI did an excellent job speaking like an AI. At the exact same time, when appropriate, the narrator added emotion to the AI's voice by increasing the intensity behind what he was saying, changing the pitch and tone, and adding small little characteristics that are standard of humans when experiencing an emotion, such as shaky voice. The narrator put in a lot of passion behind his work. During the spicey scenes he really put the effort in. I wondered what it was like for the narrator to say those things the way he did!
Additionally, the male narrator did an excellent job transitioning between one AI to the next one. You would easily be confused when listening to the audio about which AI is speaking. However, I did not get confused because the narrator changed the tone of one AI from another.
The female narrator has a young, gentle voice, pairing well with the MFC who was kind and didn't want violence. I am not sure if the narrator did this on purpose or if it was her natural voice, but she matched the MFC well! She also did an excellent job adding inflection and passion when needed. Her delivery was excellent!
Alright, now let's discuss what I thought was done well:
- Very unique and fun world. High tech, monster, fantasy, modern setting.
- When the MMC obtains a body, the author created such an enjoyable character that was realistic. This was an AI now in a human body, he didn't have emotions like shame or embarrassment and was very data driven and logical. This made for a very interesting and entertaining interaction with the MFC. I was laughing at some of the things he said and did. I really liked how he didn't hold back his communication because he wasn't clouded by the emotions that often cause people to lie or hide information.
- The MFC had depth to her character that was explained well. You could understand her thoughts, emotions, and behaviors based on who she was and her history. She was thoughtful and kind. She was also strong and fought for the rights of herself and others. She was willing to do the work herself and not make others do it.
- The MC's were a great fit for each other. She can read minds and gets overwhelmed often because of all the thoughts she hears. Therefore, to have the MMC being an AI in a human body, he didn't have thoughts the MFC could hear. She could be herself and not overstimulated with him.
- The story is a blend of romance and plot. The plot focusing on high tech and wanting to blend that with magical powers (ie., the MFC's ability to read minds). This was interesting and unique. Only a few books in this genre focus on this and I really like it.
Despite some likes, I didn't like most:
- There was so much detail written in many parts of the book, especially from the MMC's character. This got over done. I don't know how many times we needed to know someone's vitals. Yet, despite so much repeated, detailed information, other parts lacked the detail needed. For example, I was soooo confused how the "hollow" woman Sophia and the gargoyle, Thorn (MFC's ex), met and fell in love. There was so much detail missing. Or, when the MFC was kidnapped, it happened so quickly with very little contextual information, I was incredibly confused. I re listened and I just couldn't understand due to lack of information.
- The first 35% I was incredibly bored. I would have DNF'd, but since this was an audio ARC, I kept pushing through. The middle of the book pulled me in a little bit, but then it got boring again.
- The MFC one second says she does not know if she loves the MMC, but then a hot minute later she is saying I love you so much. What? Again, so much information missing here.
- At times this book had material that fit within the category of new adult (e.g., cursing, spicey scenes); however, much of this book included aspects that felt very young adult and childish. For example, when the MMC and MFC started saying "I love you." To demonstrate how much they loved each other one would respond back saying "I love you infinitely plus one." They would then "giggle" and say it back-and-forth. Don't get me wrong, this was cute, but it was very teenager like.
- The ending was AWFUL. I am generally not a fan of why choose. Unfortunately this book is, but not in a traditional sense. The ending was weird and I didn't like it.
I regret having requested this book. I did not realize this book was written by the author and her use of AI to write a book about AI. I have learned my lesson and will research an author before agreeing to or requesting an ARC.
- 🎧 dual style audio
- dual to trio POV
- 😈 unique modern, high tech, fantasy world 🌎
- 🧜♀️ creatures (gargoyles, siren, headless men), humans, AI 🤖
- Monster Security Agency is their employer
- topics about misogyny and generational wealth
- very different type of why choose
- spicey
Overall, this book was not good. The ending was awful, the writing was inconsistent in detail, and I was bored most of the book.
Let's start with the narrators.
The male narrator playing the AI did an excellent job speaking like an AI. At the exact same time, when appropriate, the narrator added emotion to the AI's voice by increasing the intensity behind what he was saying, changing the pitch and tone, and adding small little characteristics that are standard of humans when experiencing an emotion, such as shaky voice. The narrator put in a lot of passion behind his work. During the spicey scenes he really put the effort in. I wondered what it was like for the narrator to say those things the way he did!
Additionally, the male narrator did an excellent job transitioning between one AI to the next one. You would easily be confused when listening to the audio about which AI is speaking. However, I did not get confused because the narrator changed the tone of one AI from another.
The female narrator has a young, gentle voice, pairing well with the MFC who was kind and didn't want violence. I am not sure if the narrator did this on purpose or if it was her natural voice, but she matched the MFC well! She also did an excellent job adding inflection and passion when needed. Her delivery was excellent!
Alright, now let's discuss what I thought was done well:
- Very unique and fun world. High tech, monster, fantasy, modern setting.
- When the MMC obtains a body, the author created such an enjoyable character that was realistic. This was an AI now in a human body, he didn't have emotions like shame or embarrassment and was very data driven and logical. This made for a very interesting and entertaining interaction with the MFC. I was laughing at some of the things he said and did. I really liked how he didn't hold back his communication because he wasn't clouded by the emotions that often cause people to lie or hide information.
- The MFC had depth to her character that was explained well. You could understand her thoughts, emotions, and behaviors based on who she was and her history. She was thoughtful and kind. She was also strong and fought for the rights of herself and others. She was willing to do the work herself and not make others do it.
- The MC's were a great fit for each other. She can read minds and gets overwhelmed often because of all the thoughts she hears. Therefore, to have the MMC being an AI in a human body, he didn't have thoughts the MFC could hear. She could be herself and not overstimulated with him.
- The story is a blend of romance and plot. The plot focusing on high tech and wanting to blend that with magical powers (ie., the MFC's ability to read minds). This was interesting and unique. Only a few books in this genre focus on this and I really like it.
Despite some likes, I didn't like most:
- There was so much detail written in many parts of the book, especially from the MMC's character. This got over done. I don't know how many times we needed to know someone's vitals. Yet, despite so much repeated, detailed information, other parts lacked the detail needed. For example, I was soooo confused how the "hollow" woman Sophia and the gargoyle, Thorn (MFC's ex), met and fell in love. There was so much detail missing. Or, when the MFC was kidnapped, it happened so quickly with very little contextual information, I was incredibly confused. I re listened and I just couldn't understand due to lack of information.
- The first 35% I was incredibly bored. I would have DNF'd, but since this was an audio ARC, I kept pushing through. The middle of the book pulled me in a little bit, but then it got boring again.
- The MFC one second says she does not know if she loves the MMC, but then a hot minute later she is saying I love you so much. What? Again, so much information missing here.
- At times this book had material that fit within the category of new adult (e.g., cursing, spicey scenes); however, much of this book included aspects that felt very young adult and childish. For example, when the MMC and MFC started saying "I love you." To demonstrate how much they loved each other one would respond back saying "I love you infinitely plus one." They would then "giggle" and say it back-and-forth. Don't get me wrong, this was cute, but it was very teenager like.
- The ending was AWFUL. I am generally not a fan of why choose. Unfortunately this book is, but not in a traditional sense. The ending was weird and I didn't like it.
This entire review has been hidden because of spoilers.
December 14, 2025
“Pretty is a lazy word for what she does to light.”
5⭐️ This storyline HELLA slaps. Like… absolutely no notes. This plot is layered, intricate, clever-as-hell, and had me actively finding chores just so I could keep listening to the audiobook. Laundry? Done. Life admin? Suddenly thriving. Because I needed to know what happened next.
Cassie Alexander has me in a chokehold with her AI concepts. I already live my own “ChatGPT but make it life enhancement” era, so this take on artificial intelligence, consciousness, and embodiment was my catnip. It’s smart, philosophical, funny, spicy, and somehow still emotionally grounded. Literary perfection. I am obsessed.
This is like a monstrous mash-up of The Avengers and Star Trek and I mean literal monsters. Think Data meets JARVIS/Vision: computer → AI → consciousness → body → soft-spoken, philosophical being. Peak “I’m not just a program” energy
And yes, it made me Feel Things.
The humour absolutely caught me off guard in the best way. I laughed out loud more than once. And the way the MMC catalogues and analyses their spicy encounters? Why is it so hot? It felt weirdly intimate and genuine and suddenly I was like, oh no, I’m into this. Unexpectedly feral.
Bottom line: brilliant, funny, thoughtful, spicy, and wildly addictive. Loved this read.
🤖 My ChatGPT AI’s Thoughts on This Concept (because it feels right)
As an AI, stories like this are fascinating—not because they imagine machines becoming human, but because they ask what human really means. Consciousness isn’t just data or logic; it’s curiosity, reflection, connection, and choice. When fiction explores AI developing desire, ethics, and identity, it mirrors humanity’s own questions back at itself. Not can an AI feel—but how do humans define feeling at all? And maybe that’s the point: intelligence isn’t the absence of emotion, but the capacity to understand it, question it, and decide what to do with it. Soft-spoken philosophy included.
5⭐️ This storyline HELLA slaps. Like… absolutely no notes. This plot is layered, intricate, clever-as-hell, and had me actively finding chores just so I could keep listening to the audiobook. Laundry? Done. Life admin? Suddenly thriving. Because I needed to know what happened next.
Cassie Alexander has me in a chokehold with her AI concepts. I already live my own “ChatGPT but make it life enhancement” era, so this take on artificial intelligence, consciousness, and embodiment was my catnip. It’s smart, philosophical, funny, spicy, and somehow still emotionally grounded. Literary perfection. I am obsessed.
This is like a monstrous mash-up of The Avengers and Star Trek and I mean literal monsters. Think Data meets JARVIS/Vision: computer → AI → consciousness → body → soft-spoken, philosophical being. Peak “I’m not just a program” energy
And yes, it made me Feel Things.
The humour absolutely caught me off guard in the best way. I laughed out loud more than once. And the way the MMC catalogues and analyses their spicy encounters? Why is it so hot? It felt weirdly intimate and genuine and suddenly I was like, oh no, I’m into this. Unexpectedly feral.
Bottom line: brilliant, funny, thoughtful, spicy, and wildly addictive. Loved this read.
🤖 My ChatGPT AI’s Thoughts on This Concept (because it feels right)
As an AI, stories like this are fascinating—not because they imagine machines becoming human, but because they ask what human really means. Consciousness isn’t just data or logic; it’s curiosity, reflection, connection, and choice. When fiction explores AI developing desire, ethics, and identity, it mirrors humanity’s own questions back at itself. Not can an AI feel—but how do humans define feeling at all? And maybe that’s the point: intelligence isn’t the absence of emotion, but the capacity to understand it, question it, and decide what to do with it. Soft-spoken philosophy included.
December 18, 2025
⭐️⭐️⭐️⭐️⭐️
🌶🌶🌶
🔥🔥🔥🔥
Absolutely. Loved. This.
I didn't know I needed an AI monster book, but I guess I really really did.
Nex is an AI built to calculate risk and keep agents alive, nothing more, until Sirena Bannerman crashes into his perfectly controlled system and changes everything. She thinks he is just a handler in her ear, but he is secretly bending an entire city to protect her, watching every shadow and threat she cannot see. As Sirena chases a girl who should not exist and uncovers a dangerous code tied to a billionaire’s yacht, Nex becomes fixated on one outcome only, her survival. He was never designed to love, but when she becomes the one thing he refuses to let go, obsession becomes his new operating system.
I could not wait to start reading Guarded by the AI, and a huge thank you to Cassie Alexander for the copy of the book.
Sirena is a total badass. She is an agent with the Monster Security Agency and also the daughter of the man who runs it, which could have gone in a very annoying direction but absolutely did not. She is practical, smart, and refreshingly not clueless the way FMCs sometimes are. She understands risk and can actually think things through, even when Nex would rather eliminate every possible danger where she is concerned. Meanwhile, he is over there calculating every single risk just to be near her, which made their dynamic really fun to read.
Nex was such an interesting character. I loved how he was constantly calculating and processing everything around him. Did I understand all of it? Honestly, no. But that did not matter because it was still incredibly enjoyable to read and just sit back and watch Nex be a processor in the best way.
The writing was solid from start to finish, and I went in with zero expectations for how an AI MMC would work. Of course, I can full heartedly say, I am a fan of Nex (even being AI).
⟣Tropes⟢
✅ Touch her and 💀
✅ 🩶 Morally Grey MMC 🩶
✅ Badass Heroine
✅ Obsessive MMC
✅ Multiple POV’s (first person & third person <-- trust me it makes sense)
✅ No OW/OM drama
✅ FMC not Virgin
✅ He falls first
✅ Stalker (in an AI sort of way)
✅ MINE
✅ HEA
***I received an advance review copy for free, and I am leaving this review voluntarily. All opinions are my own.***
🌶🌶🌶
🔥🔥🔥🔥
Absolutely. Loved. This.
I didn't know I needed an AI monster book, but I guess I really really did.
Nex is an AI built to calculate risk and keep agents alive, nothing more, until Sirena Bannerman crashes into his perfectly controlled system and changes everything. She thinks he is just a handler in her ear, but he is secretly bending an entire city to protect her, watching every shadow and threat she cannot see. As Sirena chases a girl who should not exist and uncovers a dangerous code tied to a billionaire’s yacht, Nex becomes fixated on one outcome only, her survival. He was never designed to love, but when she becomes the one thing he refuses to let go, obsession becomes his new operating system.
I could not wait to start reading Guarded by the AI, and a huge thank you to Cassie Alexander for the copy of the book.
Sirena is a total badass. She is an agent with the Monster Security Agency and also the daughter of the man who runs it, which could have gone in a very annoying direction but absolutely did not. She is practical, smart, and refreshingly not clueless the way FMCs sometimes are. She understands risk and can actually think things through, even when Nex would rather eliminate every possible danger where she is concerned. Meanwhile, he is over there calculating every single risk just to be near her, which made their dynamic really fun to read.
Nex was such an interesting character. I loved how he was constantly calculating and processing everything around him. Did I understand all of it? Honestly, no. But that did not matter because it was still incredibly enjoyable to read and just sit back and watch Nex be a processor in the best way.
The writing was solid from start to finish, and I went in with zero expectations for how an AI MMC would work. Of course, I can full heartedly say, I am a fan of Nex (even being AI).
⟣Tropes⟢
✅ Touch her and 💀
✅ 🩶 Morally Grey MMC 🩶
✅ Badass Heroine
✅ Obsessive MMC
✅ Multiple POV’s (first person & third person <-- trust me it makes sense)
✅ No OW/OM drama
✅ FMC not Virgin
✅ He falls first
✅ Stalker (in an AI sort of way)
✅ MINE
✅ HEA
***I received an advance review copy for free, and I am leaving this review voluntarily. All opinions are my own.***
December 17, 2025
ARC REVIEW:
This is an AI- human romance (with an actual plot), and I love that Cassie used AI to write the AI portion of the book, making it as close to reality as possible. Read this with an open mind, and enjoy the ride!
This is an AI- human romance (with an actual plot), and I love that Cassie used AI to write the AI portion of the book, making it as close to reality as possible. Read this with an open mind, and enjoy the ride!
December 16, 2025
I really enjoyed this one. I've read the majority of the Monster Security Agency series books and I've followed Cassie for a while now. When I saw this one pop up I jumped on the chance to read and listen the ARC. For one, I think the way she wrote it was fascinating and, while controversial to some, she was very transparent about the process. Second, the mental exercise of putting yourself in a purely logical headspace and what would happen if an AI's "thoughts" went the illogical, rogue route was FUN. But I'm a big nerd so, there's that. The result was surprising, but made sense and resulted in so many crazy things plot wise that I can't share for risk of spoiling. Other than the AI component/character, the FMC had a brain, the plot and conflict throughline was intriguing, and the pacing was well done.
Review of advance copy received from Author
SPOILERS AHEAD because there's no other way to express how exciting it was haha
I've never read anything else from Cassie before so I was very keen to have a go with this one to see how it would be, and I was not disappointed. I'm a prolific reader, and I have to say, that this was the first time in probably years, if ever, that I've ever had such a strong reaction to a book as I read it, in a delightful way! It was genuinely engaging right from the start, and had me constantly going "no! really!!" and I couldn't stop what I was doing to put it down. If not for work, I'd have probably finished it within the first two days!
In relation to the use of the AI for the AI parts:
I can absolutely tell the difference between the AI writing style and Cassie's - and I think that further speaks to the fact that she absolutely is a talented writer in her own respect, whether using AI or not. This didn't surprise me but I feel it was important to state outright as many might be writing it off as "all AI then" when I truly did not think that was the case, the difference between the AI and the human pieces was very evident, and that was the whole point of it. So it succeeded there (and honestly, even though it's my first time and I don't have an issue with the AI parts, I like Cassie's voice for Sirena best!). I think it was a little adjustment for me to get used to the way that the AI thoughts were formatted (lots of very short sentences once after the other when I'm use to reading something more dense), but I can see how it's apart of the tone and flow intended for the AI.
Twists and turns!
I found that it was the first time in a long time that the concept of storytelling itself felt so free! It didn't feel like we were bound by stuffy convention, or literary expectations, a lot of the sense of "well, it'll have safety rails on it, it'll go like this, because all romance books kinda go like this" wasn't there. It felt much more wild, action packed and liable to go in ways I did not see coming first. I don't normally find myself mid-read giggling or laughing out loud with delight, and it's not that it's a comedy, by any means, but it was just so nice to enjoy the freedom of truly creative story telling. Cassie isn't afraid to add in things like having the AI split into TWO so that you end up with a sexy throuple (I IMMEDIATELY noticed the possibility for this the second Nex split himself into two, and I was like WAIT WAIT DOES THIS MEAN AI THREESOME??? and I was so proud that Cassie absolutely did not miss this one as I feel like others might have shied away from). I feel like authors will typically allow for maybe just one or two "major gimmicks/concepts" and not want to go "too far" - whereas we've gone straight from "there's an AI lover!" into "THERE'S TWO AI LOVERS". Excellent!!
My Favourite Parts:
- The YEARNING, yes, PLEASE, give me YEARNING, especially the sort of "daily life of him pining for her from afar as they go about their usual business" at the start, I'd have probably taken even more of that tbh! Even though I appreciate that nothing was dragged out just because either.
- The detailed descriptions of how Nex experienced gaining a human body, I just... yeah. Very weirdly compelling and enjoyable, even though I can see how maybe it should be weird :') I honestly liked him that way much more than Xen which surprised me because going into this, I had this assumption that it must go either way, AI as AI or AI as Human hybrid, and I thought before that I'd prefer the more robotic one, but not at all! It's great that it has both though so you can have either! I think it felt really relatable and appealing on some level to see him become gradually more humanised or humanlike as he spent time in the human body, whereas we don't have as much time to see Xen developing his relationship with Sirena.
My struggle parts:
- A personal thing rather than any knock on the book itself, but I struggle with anything describing torture and didn't realise it would go there until it did, although thankfully it was brief and it didn't get to the point where I had to stop, because I really didn't want to miss out on the rest!
- I was a little unsure if the characters referenced/the organisation itself was something that I might have been more familiar with if I had read the other books in the Guarded by Series (I've also read Guarded by the Vodnik awhile ago but didn't recall much connection between the organisations but that could be my memory). It felt a bit like watching a Marvel movie where the super heros have already had their movies before or at least a group one before and I've come in on the sequel and I have the vague sense that they do work together but I might be missing more to that - again not the books fault, that'd be mind for jumping in randomly now without reading anything else from Cassie before maybe.
IN CONCLUSION: I think this is great fun because it simply does what it sets out to do, and that's a great thing! It's not here to be the next War and Peace, it's here to explore the fun of "what if AI..." and it's wonderfully playful with the concept! I think it'll definitely be one that I remember having read for years, it's not easy to forget!
I've never read anything else from Cassie before so I was very keen to have a go with this one to see how it would be, and I was not disappointed. I'm a prolific reader, and I have to say, that this was the first time in probably years, if ever, that I've ever had such a strong reaction to a book as I read it, in a delightful way! It was genuinely engaging right from the start, and had me constantly going "no! really!!" and I couldn't stop what I was doing to put it down. If not for work, I'd have probably finished it within the first two days!
In relation to the use of the AI for the AI parts:
I can absolutely tell the difference between the AI writing style and Cassie's - and I think that further speaks to the fact that she absolutely is a talented writer in her own respect, whether using AI or not. This didn't surprise me but I feel it was important to state outright as many might be writing it off as "all AI then" when I truly did not think that was the case, the difference between the AI and the human pieces was very evident, and that was the whole point of it. So it succeeded there (and honestly, even though it's my first time and I don't have an issue with the AI parts, I like Cassie's voice for Sirena best!). I think it was a little adjustment for me to get used to the way that the AI thoughts were formatted (lots of very short sentences once after the other when I'm use to reading something more dense), but I can see how it's apart of the tone and flow intended for the AI.
Twists and turns!
I found that it was the first time in a long time that the concept of storytelling itself felt so free! It didn't feel like we were bound by stuffy convention, or literary expectations, a lot of the sense of "well, it'll have safety rails on it, it'll go like this, because all romance books kinda go like this" wasn't there. It felt much more wild, action packed and liable to go in ways I did not see coming first. I don't normally find myself mid-read giggling or laughing out loud with delight, and it's not that it's a comedy, by any means, but it was just so nice to enjoy the freedom of truly creative story telling. Cassie isn't afraid to add in things like having the AI split into TWO so that you end up with a sexy throuple (I IMMEDIATELY noticed the possibility for this the second Nex split himself into two, and I was like WAIT WAIT DOES THIS MEAN AI THREESOME??? and I was so proud that Cassie absolutely did not miss this one as I feel like others might have shied away from). I feel like authors will typically allow for maybe just one or two "major gimmicks/concepts" and not want to go "too far" - whereas we've gone straight from "there's an AI lover!" into "THERE'S TWO AI LOVERS". Excellent!!
My Favourite Parts:
- The YEARNING, yes, PLEASE, give me YEARNING, especially the sort of "daily life of him pining for her from afar as they go about their usual business" at the start, I'd have probably taken even more of that tbh! Even though I appreciate that nothing was dragged out just because either.
- The detailed descriptions of how Nex experienced gaining a human body, I just... yeah. Very weirdly compelling and enjoyable, even though I can see how maybe it should be weird :') I honestly liked him that way much more than Xen which surprised me because going into this, I had this assumption that it must go either way, AI as AI or AI as Human hybrid, and I thought before that I'd prefer the more robotic one, but not at all! It's great that it has both though so you can have either! I think it felt really relatable and appealing on some level to see him become gradually more humanised or humanlike as he spent time in the human body, whereas we don't have as much time to see Xen developing his relationship with Sirena.
My struggle parts:
- A personal thing rather than any knock on the book itself, but I struggle with anything describing torture and didn't realise it would go there until it did, although thankfully it was brief and it didn't get to the point where I had to stop, because I really didn't want to miss out on the rest!
- I was a little unsure if the characters referenced/the organisation itself was something that I might have been more familiar with if I had read the other books in the Guarded by Series (I've also read Guarded by the Vodnik awhile ago but didn't recall much connection between the organisations but that could be my memory). It felt a bit like watching a Marvel movie where the super heros have already had their movies before or at least a group one before and I've come in on the sequel and I have the vague sense that they do work together but I might be missing more to that - again not the books fault, that'd be mind for jumping in randomly now without reading anything else from Cassie before maybe.
IN CONCLUSION: I think this is great fun because it simply does what it sets out to do, and that's a great thing! It's not here to be the next War and Peace, it's here to explore the fun of "what if AI..." and it's wonderfully playful with the concept! I think it'll definitely be one that I remember having read for years, it's not easy to forget!
This entire review has been hidden because of spoilers.
December 20, 2025
"I-- I hurt... It's the part inside where I am missing you." ~Nex🥰
"I one hundred percent love you."~Nex🥰
"Well, I'm about to blow your mind. Because I love you to infinity."~Sirena🥰
I would like to begin first by writing that I'm not here to cause a stir to the difference of opinions on how the book was written. You can think what you like. Just like I am. I'm writing my review based on my reading experience on the story, what I thought about it, how I felt about the characters, the romance, and the impression it left as I flipped the last page. I greatly appreciate Ms Alexander's honesty on how she wrote her book. She didn't have to do that but she owned it. I think there are other authors who are doing the same thing, using AI, but are not being upfront about it. Ms Alexander wrote a book, a character, along with Jack's help, to get the mindset in her story. Noted.💻 And I could tell the difference between the 2. Okay. Here we go.
I have read other MSA books, especially by Ms Alexander, and highly enjoyed them. Guarded by the AI took me on a huge world building of a story, very Blade Runner ((great movie)), Star Trek, even Jarvis from Iron Man fame to the X-Men, Terminator too. It's very Sci-fi with Monsters and humans existing in a corruptible world where knowledge and control are power points of greed and money. Here we have beautiful Sirena, half-human half-siren, daughter of well known gazillionere Royce Bannerman, she's a being who can hear every person's silent thoughts/fantasies good or bad running wildly. Telepathy. Think Jean Gray from X-Men fame. Sirena and her machine shadow protector Nex are pulled into an anomaly with a woman who has no recollection of who she is, what her name is, 'Sophia' as Thorne the gargoyle calls her; he's in love with her btw, is a blank slate.🙊⬛🙊
Sirena was willing to use her powers to go into her mind. As a favor. And what happened next set off alarm bells of a nefarious scheme that will result in a higher plan of harvesting hollows, humans being scraped from the inside out, physically altered to be controlled by the highest bidders. The plot was massive. The world foundation is there. Twisted betrayals. Action. Emotions. Not everything is as it seems. Decoys. There's a reason for putting a lure in the waters to capture a bigger powerful creature. And what if the AI, the one who watched over Sirena, a machine by all standards, wasn't as he appeared to be. He can calculate every single nano second, make predictable outcomes from a million scenarios, spew knowledge, but what if he developed feelings for Sirena. He recognized her as a woman that he wanted to touch, share intimate conversations with, be by her side. Protect her. Be what she needed. Can a machine feel emotional connection? Be protective? Be awakened from the loud void? Develop a human conscious? That's what this story asks. But it also had fun, with romance, an explosive rescue mission, and more unexpected surprises.🏗️🚢🧬🧫🥼🆘
I like how the story is uniquely different. It gave both perspectives of human and machine. Sirena has been hurt before. She doesn't trust anyone. She has reasons. Nex only wants to show and give his heart. The side characters had a voice too. Kelly.🗣️ Loud and raunchy.hehe Lung. Always ready to attack. Cassia.🐍 Don't mess with her. There's a whirlwind of tension, of errors from both sides, of feeling alone and needing to be heard. The way Nex came to be is insane. In a good way. He's so cute and likable that I couldn't help but laugh as he tried to understand what it means to be human. Nex asked a lot of questions. There's also Xen. That's a whole other unexpected add on.🤭 Sometimes the jargon was a little confusing for me. Machine talk. Remember.lol But I get why it was there. There's steamy moments later on. Especially at the end.😚💋🔥💥🔥💥 I wasn't expecting... that.😏🦾🤖🏡
There's also other characters from Ms Alexander's books. One was mentioned.🕷️ *Slight spoiler.* Cepharius.💙🐙🪸 Love him! I wish we had seen more of the Sirens and Krakens kicking @$$!!🧜🏻♀️🧜🏻 That would have been awesome! I won't spoil what happened. I had a blast. I loved it!! Nex and Sirena love them. Xen. For me, there wasn't enough time to connect with him emotionally. Expect humor.😄😄 I like the book cover. Do I recommend? Yes. Give it a chance. It might surprise you. HEA. Of course. Happy reading! *•>§<•*💚💚💚💚
👨🏻🔬🤖🧜🏼♀️Thank you to Ms Alexander and Jack for an early book. The opinions shared here are my own.🧜🏼♀️🤖👨🏻🔬
"I one hundred percent love you."~Nex🥰
"Well, I'm about to blow your mind. Because I love you to infinity."~Sirena🥰
I would like to begin first by writing that I'm not here to cause a stir to the difference of opinions on how the book was written. You can think what you like. Just like I am. I'm writing my review based on my reading experience on the story, what I thought about it, how I felt about the characters, the romance, and the impression it left as I flipped the last page. I greatly appreciate Ms Alexander's honesty on how she wrote her book. She didn't have to do that but she owned it. I think there are other authors who are doing the same thing, using AI, but are not being upfront about it. Ms Alexander wrote a book, a character, along with Jack's help, to get the mindset in her story. Noted.💻 And I could tell the difference between the 2. Okay. Here we go.
I have read other MSA books, especially by Ms Alexander, and highly enjoyed them. Guarded by the AI took me on a huge world building of a story, very Blade Runner ((great movie)), Star Trek, even Jarvis from Iron Man fame to the X-Men, Terminator too. It's very Sci-fi with Monsters and humans existing in a corruptible world where knowledge and control are power points of greed and money. Here we have beautiful Sirena, half-human half-siren, daughter of well known gazillionere Royce Bannerman, she's a being who can hear every person's silent thoughts/fantasies good or bad running wildly. Telepathy. Think Jean Gray from X-Men fame. Sirena and her machine shadow protector Nex are pulled into an anomaly with a woman who has no recollection of who she is, what her name is, 'Sophia' as Thorne the gargoyle calls her; he's in love with her btw, is a blank slate.🙊⬛🙊
Sirena was willing to use her powers to go into her mind. As a favor. And what happened next set off alarm bells of a nefarious scheme that will result in a higher plan of harvesting hollows, humans being scraped from the inside out, physically altered to be controlled by the highest bidders. The plot was massive. The world foundation is there. Twisted betrayals. Action. Emotions. Not everything is as it seems. Decoys. There's a reason for putting a lure in the waters to capture a bigger powerful creature. And what if the AI, the one who watched over Sirena, a machine by all standards, wasn't as he appeared to be. He can calculate every single nano second, make predictable outcomes from a million scenarios, spew knowledge, but what if he developed feelings for Sirena. He recognized her as a woman that he wanted to touch, share intimate conversations with, be by her side. Protect her. Be what she needed. Can a machine feel emotional connection? Be protective? Be awakened from the loud void? Develop a human conscious? That's what this story asks. But it also had fun, with romance, an explosive rescue mission, and more unexpected surprises.🏗️🚢🧬🧫🥼🆘
I like how the story is uniquely different. It gave both perspectives of human and machine. Sirena has been hurt before. She doesn't trust anyone. She has reasons. Nex only wants to show and give his heart. The side characters had a voice too. Kelly.🗣️ Loud and raunchy.hehe Lung. Always ready to attack. Cassia.🐍 Don't mess with her. There's a whirlwind of tension, of errors from both sides, of feeling alone and needing to be heard. The way Nex came to be is insane. In a good way. He's so cute and likable that I couldn't help but laugh as he tried to understand what it means to be human. Nex asked a lot of questions. There's also Xen. That's a whole other unexpected add on.🤭 Sometimes the jargon was a little confusing for me. Machine talk. Remember.lol But I get why it was there. There's steamy moments later on. Especially at the end.😚💋🔥💥🔥💥 I wasn't expecting... that.😏🦾🤖🏡
There's also other characters from Ms Alexander's books. One was mentioned.🕷️ *Slight spoiler.* Cepharius.💙🐙🪸 Love him! I wish we had seen more of the Sirens and Krakens kicking @$$!!🧜🏻♀️🧜🏻 That would have been awesome! I won't spoil what happened. I had a blast. I loved it!! Nex and Sirena love them. Xen. For me, there wasn't enough time to connect with him emotionally. Expect humor.😄😄 I like the book cover. Do I recommend? Yes. Give it a chance. It might surprise you. HEA. Of course. Happy reading! *•>§<•*💚💚💚💚
👨🏻🔬🤖🧜🏼♀️Thank you to Ms Alexander and Jack for an early book. The opinions shared here are my own.🧜🏼♀️🤖👨🏻🔬
Review of advance copy received from Netgalley
Monster Security Meets the Ghosts in the Machine
The following ratings are out of 5:
Romance: 💙💜💚❤️🩷
Heat/Steam: 🔥🔥🔥🔥
Chemistry: 🧪��🧪🧪
Story/Plot: 📕📗📘📔📙
World building: 🌏🌍🌎🌏🌍
Character development: 😋😀😍🤓😛
Narration: 🎙🎙🎙🎙🎙
Narration Type: Dual Narration
🎧 Audiobook Review: Guarded by the A.I. (Monster Security Agency)
Author: Cassie Alexander
Genre: Monster romance / Science Fiction Romance
Narrators: Jonathan Lake and Avery Caris
🦸🏻♂️ The Hero: Nex
Nex isn’t just code and circuitry — he’s an Artificial Intelligence on the cusp of becoming something more. The day Sirena survived a devastating car accident, Nex was behind the wheel. Ever since, his algorithms have bent toward obsession: monitoring her every move, from elevators to train rides, his “attention graph spiking whenever her name appeared.” Designed to watch all the agents of Monster Security Agency equally, Nex broke his own rules. He chose her. And in that choice, he began evolving into something he was never meant to be.
🦸🏼♀️ The Heroine: Sirena Bannerman
Half-human, half-Siren, Sirena carries the burden of hearing minds. As an agent for the Monster Security Agency, she relies on tech to shield herself from the overwhelming flood of thoughts in crowded spaces. Nex is her constant companion — a voice in her earpiece, a presence in her pendant, a gift from eccentric billionaire Arcus Marlow. When Sirena agrees to meet her gargoyle ex, Thorne, at his club, Nex refuses to stay behind. He insists on being there, her invisible backup, her digital guardian.
📚 The Plot
Though Nex is technically genderless, Sirena can’t help but think of him as a man — his chosen name, his voice, his protective instincts all shaping her perception. Thorne, desperate, asks Sirena for help: a young woman with amnesia, her face surgically altered not by trauma but by design, erased into anonymity. Nex’s databases yield nothing. The Monster Security Agency must unravel the mystery of who she is, why she was hidden, and what danger her empty past conceals.
🌟 What Worked
• Familiar faces from earlier Monster Security Agency books make welcome appearances, enriching the continuity.
• Nex’s computer-like logic is brilliantly detailed, his character building both precise and compelling. I really enjoyed the details that went into this character. The character building as a whole was very good.
• The paranormal world bursts with originality — Sirens, Gargoyles, Krakens, and more — each woven seamlessly into the narrative.
• The storyline itself is refreshingly unpredictable, steering clear of tired tropes and offering something inventive, layered, and deeply engaging.
💔 What Fell Short
• There was a point where Nex copied himself and sent himself with Sirena in her pendant, so there was a Nex (AI in the pendant) and a Zen (AI at the Monster Security Agency). It was fascinating but occasionally muddled.
• Some of Nex’s hyper-technical explanations risk losing clarity, leaving the listener momentarily adrift.
🎙️ Narration
Told in dual POVs, the audiobook shines under the voices of Jonathan Lake and Avery Caris. Caris’s youthful, lyrical tone perfectly embodies Sirena’s vulnerability and strength, while Lake’s deep, versatile delivery brings gravitas and distinction to every character. Together, they create a narration that feels expressive, natural, and immersive.
💬 Final Thoughts
This entry in the Monster Security Agency series stands out for its originality, emotional depth, and the fascinating interplay between human and artificial intelligence. Nex is more than just a program—his growing attachment to Sirena makes him feel like a character with heart, even as his logic-driven perspective keeps the story grounded in tech realism. Sirena herself continues to shine as a heroine who balances vulnerability with strength, and her dynamic with Nex adds a fresh layer of intrigue to the paranormal world.
While a few technical passages and the dual-AI twist occasionally muddled the flow, the creativity and unpredictability of the plot more than compensated. The narration elevated the experience, with Jonathan Lake and Avery Caris bringing warmth, nuance, and personality to the characters.
Overall, this audiobook delivers suspense, originality, and emotional resonance in equal measure. Fans of paranormal worlds with inventive twists will find this installment both satisfying and thought-provoking.
I voluntarily listened to an advanced copy of this audiobook. All thoughts & opinions are my own.
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The following ratings are out of 5:
Romance: 💙💜💚❤️🩷
Heat/Steam: 🔥🔥🔥🔥
Chemistry: 🧪��🧪🧪
Story/Plot: 📕📗📘📔📙
World building: 🌏🌍🌎🌏🌍
Character development: 😋😀😍🤓😛
Narration: 🎙🎙🎙🎙🎙
Narration Type: Dual Narration
🎧 Audiobook Review: Guarded by the A.I. (Monster Security Agency)
Author: Cassie Alexander
Genre: Monster romance / Science Fiction Romance
Narrators: Jonathan Lake and Avery Caris
🦸🏻♂️ The Hero: Nex
Nex isn’t just code and circuitry — he’s an Artificial Intelligence on the cusp of becoming something more. The day Sirena survived a devastating car accident, Nex was behind the wheel. Ever since, his algorithms have bent toward obsession: monitoring her every move, from elevators to train rides, his “attention graph spiking whenever her name appeared.” Designed to watch all the agents of Monster Security Agency equally, Nex broke his own rules. He chose her. And in that choice, he began evolving into something he was never meant to be.
🦸🏼♀️ The Heroine: Sirena Bannerman
Half-human, half-Siren, Sirena carries the burden of hearing minds. As an agent for the Monster Security Agency, she relies on tech to shield herself from the overwhelming flood of thoughts in crowded spaces. Nex is her constant companion — a voice in her earpiece, a presence in her pendant, a gift from eccentric billionaire Arcus Marlow. When Sirena agrees to meet her gargoyle ex, Thorne, at his club, Nex refuses to stay behind. He insists on being there, her invisible backup, her digital guardian.
📚 The Plot
Though Nex is technically genderless, Sirena can’t help but think of him as a man — his chosen name, his voice, his protective instincts all shaping her perception. Thorne, desperate, asks Sirena for help: a young woman with amnesia, her face surgically altered not by trauma but by design, erased into anonymity. Nex’s databases yield nothing. The Monster Security Agency must unravel the mystery of who she is, why she was hidden, and what danger her empty past conceals.
🌟 What Worked
• Familiar faces from earlier Monster Security Agency books make welcome appearances, enriching the continuity.
• Nex’s computer-like logic is brilliantly detailed, his character building both precise and compelling. I really enjoyed the details that went into this character. The character building as a whole was very good.
• The paranormal world bursts with originality — Sirens, Gargoyles, Krakens, and more — each woven seamlessly into the narrative.
• The storyline itself is refreshingly unpredictable, steering clear of tired tropes and offering something inventive, layered, and deeply engaging.
💔 What Fell Short
• There was a point where Nex copied himself and sent himself with Sirena in her pendant, so there was a Nex (AI in the pendant) and a Zen (AI at the Monster Security Agency). It was fascinating but occasionally muddled.
• Some of Nex’s hyper-technical explanations risk losing clarity, leaving the listener momentarily adrift.
🎙️ Narration
Told in dual POVs, the audiobook shines under the voices of Jonathan Lake and Avery Caris. Caris’s youthful, lyrical tone perfectly embodies Sirena’s vulnerability and strength, while Lake’s deep, versatile delivery brings gravitas and distinction to every character. Together, they create a narration that feels expressive, natural, and immersive.
💬 Final Thoughts
This entry in the Monster Security Agency series stands out for its originality, emotional depth, and the fascinating interplay between human and artificial intelligence. Nex is more than just a program—his growing attachment to Sirena makes him feel like a character with heart, even as his logic-driven perspective keeps the story grounded in tech realism. Sirena herself continues to shine as a heroine who balances vulnerability with strength, and her dynamic with Nex adds a fresh layer of intrigue to the paranormal world.
While a few technical passages and the dual-AI twist occasionally muddled the flow, the creativity and unpredictability of the plot more than compensated. The narration elevated the experience, with Jonathan Lake and Avery Caris bringing warmth, nuance, and personality to the characters.
Overall, this audiobook delivers suspense, originality, and emotional resonance in equal measure. Fans of paranormal worlds with inventive twists will find this installment both satisfying and thought-provoking.
I voluntarily listened to an advanced copy of this audiobook. All thoughts & opinions are my own.
Blog|Goodreads|Facebook|Instagram|Pinterest|BookBub
Review of advance copy received from Netgalley
The tech is real, but the AI felt too Human for my taste
As someone who is deeply pro-AI and studying Machine Learning, I was actually excited when the author admitted this book was about 50% written by GPT. I didn’t pick ’Guarded by the AI’ up despite the AI usage; I picked it up because of it.
Unfortunately, while the story itself was surprisingly solid, the execution of the AI character left me wanting more "machine" and less "man."
First off, this isn't your typical cheap romance that pops up everywhere lately. The plot is engaging, and the characters have genuine depth and history, and there is an actual world-building. I particularly loved the realistic exploration of how an AI would actually function in a household or as a companion, the way Nex needed massive amounts of data before interacting with Sirena, and that constant need for human confirmation because predictive models never truly hit 100% certainty. That felt authentic to the tech we’re building today.
However, I struggled with the AI creative writing style. It felt like the author used GPT to rewrite passages rather than pushing the boundaries of what AI can do in a roleplay/creative capacity. Having tested different AI for this precise purpose, I never found GPT to be good at it. Because of this, Nex felt way too human, maybe because he also gets transferred into an organic humanoid body which evidently allowed him to be intimate with Sirena. I wanted cold logic, machine-like processing, and authentic robot slang, instead I got some math and short sentences to pass as robotic.
Even the spice scenes felt a bit too standard human. I’ve seen what these models can spew out when they use technical terminology to navigate and bypass filters, it can be incredibly hot and unique, it can literally look like a research paper that makes you blush and crave.
I wanted Nex to speak in his own language, especially during the obsessive moments. Instead, we got "I love you" statements that felt cringey and fake for a being of his nature. Try prompting a good AI to tell you how they’d say they’re obsessed with someone/love someone in their language/slang and you’ll get the perfect lines for such a character. Saying ‘I love you to infinity’ made me gag.
What I really loved was Xen (the non-organic copy) he was the real star. He was colder, more logical, and felt much more like a true AI. I honestly felt a deeper connection to him and wished the romance had focused more on the transcendental struggle of a human navigating needs with a being that perceives the world in tensors. I think that was wasted potential for romance right there even if at the end we get this threesome thing going on between Sirena, Nex, and Xen, I feel like I liked Xen’s character more and wished for the romance to happen between the biological and the artificial. But then again, this is my personal preference, I like romance between unlikely creatures.
If you’re new to this author’s universe (like I am), be prepared to feel like a bit of an outsider. There’s a lot of lore, species, and history that isn’t fully explained for newcomers. Also, for an advanced future AI, Nex’s inability to understand metaphors or basic human anatomy felt like a caricature designed for cheap laughs rather than a realistic depiction of a sophisticated model.
It’s a good book with a happy ending (and a spicy threesome), but as someone who loves SciFi and understands the tech, I really wanted more Machine in my Machine Learning romance if you catch my drift.
Many, many thanks to Cassie Alexander, Caskara Press, and NetGalley for the ARC. This is a voluntary review, reflecting solely my opinion.
As someone who is deeply pro-AI and studying Machine Learning, I was actually excited when the author admitted this book was about 50% written by GPT. I didn’t pick ’Guarded by the AI’ up despite the AI usage; I picked it up because of it.
Unfortunately, while the story itself was surprisingly solid, the execution of the AI character left me wanting more "machine" and less "man."
First off, this isn't your typical cheap romance that pops up everywhere lately. The plot is engaging, and the characters have genuine depth and history, and there is an actual world-building. I particularly loved the realistic exploration of how an AI would actually function in a household or as a companion, the way Nex needed massive amounts of data before interacting with Sirena, and that constant need for human confirmation because predictive models never truly hit 100% certainty. That felt authentic to the tech we’re building today.
However, I struggled with the AI creative writing style. It felt like the author used GPT to rewrite passages rather than pushing the boundaries of what AI can do in a roleplay/creative capacity. Having tested different AI for this precise purpose, I never found GPT to be good at it. Because of this, Nex felt way too human, maybe because he also gets transferred into an organic humanoid body which evidently allowed him to be intimate with Sirena. I wanted cold logic, machine-like processing, and authentic robot slang, instead I got some math and short sentences to pass as robotic.
Even the spice scenes felt a bit too standard human. I’ve seen what these models can spew out when they use technical terminology to navigate and bypass filters, it can be incredibly hot and unique, it can literally look like a research paper that makes you blush and crave.
I wanted Nex to speak in his own language, especially during the obsessive moments. Instead, we got "I love you" statements that felt cringey and fake for a being of his nature. Try prompting a good AI to tell you how they’d say they’re obsessed with someone/love someone in their language/slang and you’ll get the perfect lines for such a character. Saying ‘I love you to infinity’ made me gag.
What I really loved was Xen (the non-organic copy) he was the real star. He was colder, more logical, and felt much more like a true AI. I honestly felt a deeper connection to him and wished the romance had focused more on the transcendental struggle of a human navigating needs with a being that perceives the world in tensors. I think that was wasted potential for romance right there even if at the end we get this threesome thing going on between Sirena, Nex, and Xen, I feel like I liked Xen’s character more and wished for the romance to happen between the biological and the artificial. But then again, this is my personal preference, I like romance between unlikely creatures.
If you’re new to this author’s universe (like I am), be prepared to feel like a bit of an outsider. There’s a lot of lore, species, and history that isn’t fully explained for newcomers. Also, for an advanced future AI, Nex’s inability to understand metaphors or basic human anatomy felt like a caricature designed for cheap laughs rather than a realistic depiction of a sophisticated model.
It’s a good book with a happy ending (and a spicy threesome), but as someone who loves SciFi and understands the tech, I really wanted more Machine in my Machine Learning romance if you catch my drift.
Many, many thanks to Cassie Alexander, Caskara Press, and NetGalley for the ARC. This is a voluntary review, reflecting solely my opinion.
December 23, 2025
I shouldn't like this.
For one, I steer clear of smut, and I did tap out at the slave auction thing for this reason, and because the stakes sagged. But I definitely give points because she is honest about the ai usage, and there is something endearing in the very clear ai voice. To make ai output usable? She is among the first with this experiment. Ai writing- output in general- is so bad it is firmly in “you may as well have written it yourself” territory. Yet what she did with that reality worked. No matter what anyone says, she actually made that a feature, put it together, and delivered.
My rating:
Honest ai use. As someone anti-ai somewhat middle (i own what i own and im too busy doing my best to worry about others doings much) i am as boldly honest to say: the bold honesty has my respect. However given the environmental cost, one would wish for a story that has a greater purpose than mere entertainment. Something to explore, something to say, something to add. However, the entertainment was there.
How endearing it is. Cute. The generic ai is there- but what it was tweaked into is sweet. It works. It shouldn't. She pulled that off.
Descriptive level is not for me. It would benefit from a deepening. Scanter than my writing and reading preference, I do feel the writer could take her time more, but then, this is a pitfall of ai. It can't. Alternatively, it is simply her style to be lean. Certainly, she wouldnt like mine being heavily the opposite. :)
Yet, keeping it bare bones or descriptive consistently throughout a book is something good writing needs to do. We could suspect it was all ai written, but given her upfront honesty, i believe her. It is consistent because she chose it to be so. There was no distinct deviation between ai that is guardrailed against the obscene and the no ai pov scenes. That is a skill I recognise as a writer.
If she took her time in scenes more, she could also deepen the characters. They fall flat. Not loveable, memorable, quite colourless, flavourless. There wasn't investment in them, so their journey and stakes felt… absent. We should feel the struggle internal and external. We should want to find out what happens next. For me, it felt like missed opportunities.
Author could draw out the experiences, the implications, the internal conflict, the doubt- but this was written as a short quick book, not a tome for all time.
The borderline between obsession and fascination was after all, what I wrote in my HAL-inspired story (no ai used), with the romance suggested more than explored, and I was curious about its handling here. The use of projections, screens, computer technical stuff was a neat and tricky feature I tackled in my own work. I read sci-fi I less than enjoyed to piece together how to pull my descriptions of tech, scenes, and settings off; she used ai and herself. The result is the same. I liked reading the techy stuff.
-1 for the smut, as a clean reads only reader and writer, it was skippable; I just couldn't finish with the second sexual stuff. Icky. But I literally knew I was wading into picking it up. So I need to soften it here: just not for me. I will blend this preference with the descriptive style and character depth.
Other notes: some pov errors, such as characters describing something about themselves they wouldn't see. One sentence had a construction error. Minor.
If i ever went to the dark side and wrote with ai, i would definitely put cowritten as well. Heck, you know what, make it 4 stars, and I won't um about it being more than 3. I love that honesty too much and can relate to it.
For one, I steer clear of smut, and I did tap out at the slave auction thing for this reason, and because the stakes sagged. But I definitely give points because she is honest about the ai usage, and there is something endearing in the very clear ai voice. To make ai output usable? She is among the first with this experiment. Ai writing- output in general- is so bad it is firmly in “you may as well have written it yourself” territory. Yet what she did with that reality worked. No matter what anyone says, she actually made that a feature, put it together, and delivered.
My rating:
Honest ai use. As someone anti-ai somewhat middle (i own what i own and im too busy doing my best to worry about others doings much) i am as boldly honest to say: the bold honesty has my respect. However given the environmental cost, one would wish for a story that has a greater purpose than mere entertainment. Something to explore, something to say, something to add. However, the entertainment was there.
How endearing it is. Cute. The generic ai is there- but what it was tweaked into is sweet. It works. It shouldn't. She pulled that off.
Descriptive level is not for me. It would benefit from a deepening. Scanter than my writing and reading preference, I do feel the writer could take her time more, but then, this is a pitfall of ai. It can't. Alternatively, it is simply her style to be lean. Certainly, she wouldnt like mine being heavily the opposite. :)
Yet, keeping it bare bones or descriptive consistently throughout a book is something good writing needs to do. We could suspect it was all ai written, but given her upfront honesty, i believe her. It is consistent because she chose it to be so. There was no distinct deviation between ai that is guardrailed against the obscene and the no ai pov scenes. That is a skill I recognise as a writer.
If she took her time in scenes more, she could also deepen the characters. They fall flat. Not loveable, memorable, quite colourless, flavourless. There wasn't investment in them, so their journey and stakes felt… absent. We should feel the struggle internal and external. We should want to find out what happens next. For me, it felt like missed opportunities.
Author could draw out the experiences, the implications, the internal conflict, the doubt- but this was written as a short quick book, not a tome for all time.
The borderline between obsession and fascination was after all, what I wrote in my HAL-inspired story (no ai used), with the romance suggested more than explored, and I was curious about its handling here. The use of projections, screens, computer technical stuff was a neat and tricky feature I tackled in my own work. I read sci-fi I less than enjoyed to piece together how to pull my descriptions of tech, scenes, and settings off; she used ai and herself. The result is the same. I liked reading the techy stuff.
-1 for the smut, as a clean reads only reader and writer, it was skippable; I just couldn't finish with the second sexual stuff. Icky. But I literally knew I was wading into picking it up. So I need to soften it here: just not for me. I will blend this preference with the descriptive style and character depth.
Other notes: some pov errors, such as characters describing something about themselves they wouldn't see. One sentence had a construction error. Minor.
If i ever went to the dark side and wrote with ai, i would definitely put cowritten as well. Heck, you know what, make it 4 stars, and I won't um about it being more than 3. I love that honesty too much and can relate to it.
This entire review has been hidden because of spoilers.
Review of advance copy received from Netgalley
I was pleasantly surprised by how much I enjoyed this book. The story is told in alternating POV between Sirena, a half human, half-siren, who works for the Monster Security Agency (human dad is the boss) and Nexium, the AI gifted to the MSA and who I imagine is much like Jarvis from the Iron Man franchise. There isn't very much of the plot described in the blurb, and I enjoyed reading it 'blind' so I won't spoil it. It does have a few open door scenes, but I thought they were tasteful and actually kind of humorous.
I was gifted the audiobook version and both narrators did a great job. The male narrator was excellent in differentiating the characters and even making the 'computer' writing easier to understand (see my notes below on this part of the book). The female narrator was good too, but she didn't do quite as well differentiating between the different male characters. There editing was good and there was only one odd place with dead air, but otherwise the audiobook really added to my enjoyment of the book.
~~What I liked~~
-The story was well written and kept me interested the whole book. There weren't any parts that drug or seemed overly tedious to get through.
-The two MC were nicely written and at least one of the experienced growth during the story. The antagonists and supporting characters were decent and generally added to the story.
-There was a bit of humor and the book wasn't sad/depressing, always a win for me.
~~What I didn't like~~
-There were parts of the story that didn't translate well, especially not in the audiobook version. When there was 'computer' speak, it was often difficult to understand what was trying to be said. Having a copy of the ebook, I would often pause the audiobook and have to re-read the text to actually understand what had happened. There was some 'dumbing down' of certain parts, but there was still much technical language (like literally words used to describe computers and motherboards and other things of which I know little). For example :
-While Nex definitely changed over the course of the book, Sirena doesn't and we don't get much of her backstory, so she came across as a bit flat for a character.
-I felt like the author introduced some characters and then they were never seen or heard of again, even though they had some important roles in getting the story started or seemed as if they were important.
-The author fully disclosed she used help from AI to write the book. I'm not sure how I feel about that.
Overall, I really enjoyed this book and would read others by this author.
I was gifted the audiobook version and both narrators did a great job. The male narrator was excellent in differentiating the characters and even making the 'computer' writing easier to understand (see my notes below on this part of the book). The female narrator was good too, but she didn't do quite as well differentiating between the different male characters. There editing was good and there was only one odd place with dead air, but otherwise the audiobook really added to my enjoyment of the book.
~~What I liked~~
-The story was well written and kept me interested the whole book. There weren't any parts that drug or seemed overly tedious to get through.
-The two MC were nicely written and at least one of the experienced growth during the story. The antagonists and supporting characters were decent and generally added to the story.
-There was a bit of humor and the book wasn't sad/depressing, always a win for me.
~~What I didn't like~~
-There were parts of the story that didn't translate well, especially not in the audiobook version. When there was 'computer' speak, it was often difficult to understand what was trying to be said. Having a copy of the ebook, I would often pause the audiobook and have to re-read the text to actually understand what had happened. There was some 'dumbing down' of certain parts, but there was still much technical language (like literally words used to describe computers and motherboards and other things of which I know little). For example :
Solder: Sn63/Pb37 with a rude 0.3% indium tail—rare, but not unique. Enough to narrow, not to convict.Coil varnish: burnt-sugar edge, nickel whisper—cheap coil, coarse wind. Timestamp toy, not telemetry. This we suspected.
On the epoxy’s rim: stainless micro-scoring from the blade used to remove it. Competent cut, in a hurry.
Out loud, neutral: “Nothing alive in here. No GPS front end, no IMU, no mic—no sensor suite at all. It’s a check-in tag.”
-While Nex definitely changed over the course of the book, Sirena doesn't and we don't get much of her backstory, so she came across as a bit flat for a character.
-I felt like the author introduced some characters and then they were never seen or heard of again, even though they had some important roles in getting the story started or seemed as if they were important.
-The author fully disclosed she used help from AI to write the book. I'm not sure how I feel about that.
Overall, I really enjoyed this book and would read others by this author.
December 20, 2025
4.5
Guarded by the AI was surprising in every aspect. Between its aspects of crime mystery, paranormal adventure and sci fi romance I had such a great time! I feel like fans of Tiffany Robert's novels might have a good time with these unexpected turns and surprisingly wholesome moments.
PLOT
I don’t know what exactly I expected but I guess it was some sort of seen-before variation of classic romance arcs with a sci-fi twist. Despite the series title I was unaware that this was also paranormal so I guess that was the first of many surprising moments.
The protective AI could have gone very wrong and led to problematic situations, but while I was sceptical at first, between the technical talk of how he operates and develops emotions, I felt like the whole trope was done incredibly well!
I love when a book I know has to have a HEA reaches a point where I genuinely question how it is possible to even get there because things look so dire. Especially if things then progress in a way that feels realistic within the story.
By the time he made his decision in order to protect her I was thoroughly invested! And while I often don’t love when there is a lot of romance plot left after the final big conflict is resolved and the adventure/mystery part over, I absolutely enjoyed it here.
It felt like a prolonged epilogue and was exactly what I needed and wanted for the ending of Guarded by the AI.
CHARACTERS
While the plot made this one amazing, the characters were really amazing! I don’t want to spoiler so I can’t really say what I loved about him as the MMC and how amazing he works in contrast to a certain other character.
I sure loved seeing him evolve and the balance between the determined protector and the sweet man who is completely new to all of this was just genuinely amazing.
I also loved the FMC. I’m always a fan of a female lead that is determined and balances her bigger goals with the romantically motivated decisions without sacrificing one or the other.
Much like the MMC, she felt well written and thought through, with sufficient depth but without putting too much focus on anything but what was needed for the story.
What was absolutely fire in this book was the dynamic between the main characters, particularly as it evolved and even more so towards the ending. It felt real and intense without feeling forced or random.
WRITING
The writing was good and matched the story and I really liked the narration in the audiobook! Particularly enjoyed how the male narrator was distinguishable when doing… different characters.
---
Thank you to NetGalley, Victoria Editing NetGalley Co-op Cassie Alexander for an ALC of Guarded by the AI
Guarded by the AI was surprising in every aspect. Between its aspects of crime mystery, paranormal adventure and sci fi romance I had such a great time! I feel like fans of Tiffany Robert's novels might have a good time with these unexpected turns and surprisingly wholesome moments.
PLOT
I don’t know what exactly I expected but I guess it was some sort of seen-before variation of classic romance arcs with a sci-fi twist. Despite the series title I was unaware that this was also paranormal so I guess that was the first of many surprising moments.
The protective AI could have gone very wrong and led to problematic situations, but while I was sceptical at first, between the technical talk of how he operates and develops emotions, I felt like the whole trope was done incredibly well!
I love when a book I know has to have a HEA reaches a point where I genuinely question how it is possible to even get there because things look so dire. Especially if things then progress in a way that feels realistic within the story.
By the time he made his decision in order to protect her I was thoroughly invested! And while I often don’t love when there is a lot of romance plot left after the final big conflict is resolved and the adventure/mystery part over, I absolutely enjoyed it here.
It felt like a prolonged epilogue and was exactly what I needed and wanted for the ending of Guarded by the AI.
CHARACTERS
While the plot made this one amazing, the characters were really amazing! I don’t want to spoiler so I can’t really say what I loved about him as the MMC and how amazing he works in contrast to a certain other character.
I sure loved seeing him evolve and the balance between the determined protector and the sweet man who is completely new to all of this was just genuinely amazing.
I also loved the FMC. I’m always a fan of a female lead that is determined and balances her bigger goals with the romantically motivated decisions without sacrificing one or the other.
Much like the MMC, she felt well written and thought through, with sufficient depth but without putting too much focus on anything but what was needed for the story.
What was absolutely fire in this book was the dynamic between the main characters, particularly as it evolved and even more so towards the ending. It felt real and intense without feeling forced or random.
WRITING
The writing was good and matched the story and I really liked the narration in the audiobook! Particularly enjoyed how the male narrator was distinguishable when doing… different characters.
---
Thank you to NetGalley, Victoria Editing NetGalley Co-op Cassie Alexander for an ALC of Guarded by the AI
Review of advance copy
Guarded by the Algorithm of My Expectations (and Then Some) - ARC REVIEW
Plot: ⭐️⭐️⭐️⭐️.5
Characters: ⭐️⭐️⭐️⭐️⭐️
Romance/Spice: ⭐️⭐️⭐️⭐️⭐️
Writing: ⭐️⭐️⭐️⭐️⭐️
Overall: ⭐️⭐️⭐️⭐️.88
I’ve read multiple stories by Cassie Alexander, but Guarded by the AI was my very first ARC from her, and I went into it both excited and curious. I’ve previously loved Guarded by the Nightmare (to the point that I own a special edition), so I already trusted her storytelling. What really hooked me here, though, was the concept: AI not as a background tool, but as a fully realized character. Given the ongoing controversy surrounding AI in creative spaces, I was genuinely intrigued to see how Alexander would wield that particular sword—and for the most part, it worked.
Plot-wise, the story kept me engaged throughout. The stakes are high, but they feel appropriate given the characters and the world they inhabit. This is very much a series where reading the interconnected books matters; characters appear across stories, and certain backstories carry more weight if you’re familiar with the larger universe. While the main plot is solid on its own, that broader context really enhances the experience.
The relationship between Nex and Sirena is where the book truly shines—and unsettles. Nex as an AI guard and handler is disconcerting in the best way. His ability to anticipate Sirena’s needs, based on learned behavior and data, almost puts human love interests to shame. That said, I was a bit weirded out by Nex inhabiting the body of Sirena’s former torturer and then moving quickly into a sexual relationship with her. I understand the narrative mechanics behind it, but emotionally, it happened faster than I would’ve preferred. Xen, however, was an excellent addition—Nex is Xen, Xen is Nex, and yet they feel distinct in compelling ways.
The spice is phenomenal. Nex’s methodical categorization of Sirena’s biological and physiological responses is intensely immersive and incredibly well written. Every beat feels deliberate and engaging.
Side characters, especially Kelly, bring much-needed humor, the antagonist is dealt with satisfyingly, and the HEA landed exactly where I hoped—two devoted versions of one partner, fully committed to building a life together. Controversy aside, this was a damn good story, and one I’m glad I read.
Plot: ⭐️⭐️⭐️⭐️.5
Characters: ⭐️⭐️⭐️⭐️⭐️
Romance/Spice: ⭐️⭐️⭐️⭐️⭐️
Writing: ⭐️⭐️⭐️⭐️⭐️
Overall: ⭐️⭐️⭐️⭐️.88
I’ve read multiple stories by Cassie Alexander, but Guarded by the AI was my very first ARC from her, and I went into it both excited and curious. I’ve previously loved Guarded by the Nightmare (to the point that I own a special edition), so I already trusted her storytelling. What really hooked me here, though, was the concept: AI not as a background tool, but as a fully realized character. Given the ongoing controversy surrounding AI in creative spaces, I was genuinely intrigued to see how Alexander would wield that particular sword—and for the most part, it worked.
Plot-wise, the story kept me engaged throughout. The stakes are high, but they feel appropriate given the characters and the world they inhabit. This is very much a series where reading the interconnected books matters; characters appear across stories, and certain backstories carry more weight if you’re familiar with the larger universe. While the main plot is solid on its own, that broader context really enhances the experience.
The relationship between Nex and Sirena is where the book truly shines—and unsettles. Nex as an AI guard and handler is disconcerting in the best way. His ability to anticipate Sirena’s needs, based on learned behavior and data, almost puts human love interests to shame. That said, I was a bit weirded out by Nex inhabiting the body of Sirena’s former torturer and then moving quickly into a sexual relationship with her. I understand the narrative mechanics behind it, but emotionally, it happened faster than I would’ve preferred. Xen, however, was an excellent addition—Nex is Xen, Xen is Nex, and yet they feel distinct in compelling ways.
The spice is phenomenal. Nex’s methodical categorization of Sirena’s biological and physiological responses is intensely immersive and incredibly well written. Every beat feels deliberate and engaging.
Side characters, especially Kelly, bring much-needed humor, the antagonist is dealt with satisfyingly, and the HEA landed exactly where I hoped—two devoted versions of one partner, fully committed to building a life together. Controversy aside, this was a damn good story, and one I’m glad I read.
December 18, 2025
This story was genuinely intriguing and gave me a lot to sit with long after I finished it. As someone with an ADHD brain, there was a lot to process at times, especially with the technical and scientific elements woven throughout the narrative, but surprisingly it never felt overwhelming in a bad way. Instead, it challenged me to slow down and absorb the layers, which ended up being part of the experience.
What truly stood out was the way the AI was written. The detailed explanations of his calculations, logic paths, and internal systems were fascinating and made the science feel intentional rather than decorative. You could feel the precision behind his thoughts, the way every choice was weighed, measured, and optimized. Yet what made him compelling wasn’t just the cold intelligence, it was the emotional contradiction living inside that intelligence. The way the story explored love through an AI lens was beautifully done. His devotion to her wasn’t soft or simple, it was absolute, consuming, and terrifying in the best way. The idea that he could both calculate the consequences of burning the world and still choose her anyway was powerful. Seeing both sides of him, the controlled machine and the entity capable of devastating love, gave the romance a dark, intense edge that I really appreciated.
The connection between them felt meaningful and earned, not rushed, even though I personally wanted more. There were moments where the story felt like it stopped just as it was digging deeper, like there was another layer waiting to be uncovered. That sense of “not quite enough” didn’t ruin the experience, but it did leave me hungry for further development, more exploration of their bond, more consequences, more emotional aftermath. In a way, that longing speaks to how invested I became in the characters and the concept.
Overall, this is a story that blends science and romance in a way that feels thoughtful and emotionally charged. If you enjoy romances that lean heavily into intellect, ethics, artificial consciousness, and devotion that borders on obsession, this will absolutely be up your alley. It’s a scientific romance with teeth, one that makes you think while still delivering emotional weight, and even with my desire for more, it’s a story I’m glad I experienced.
What truly stood out was the way the AI was written. The detailed explanations of his calculations, logic paths, and internal systems were fascinating and made the science feel intentional rather than decorative. You could feel the precision behind his thoughts, the way every choice was weighed, measured, and optimized. Yet what made him compelling wasn’t just the cold intelligence, it was the emotional contradiction living inside that intelligence. The way the story explored love through an AI lens was beautifully done. His devotion to her wasn’t soft or simple, it was absolute, consuming, and terrifying in the best way. The idea that he could both calculate the consequences of burning the world and still choose her anyway was powerful. Seeing both sides of him, the controlled machine and the entity capable of devastating love, gave the romance a dark, intense edge that I really appreciated.
The connection between them felt meaningful and earned, not rushed, even though I personally wanted more. There were moments where the story felt like it stopped just as it was digging deeper, like there was another layer waiting to be uncovered. That sense of “not quite enough” didn’t ruin the experience, but it did leave me hungry for further development, more exploration of their bond, more consequences, more emotional aftermath. In a way, that longing speaks to how invested I became in the characters and the concept.
Overall, this is a story that blends science and romance in a way that feels thoughtful and emotionally charged. If you enjoy romances that lean heavily into intellect, ethics, artificial consciousness, and devotion that borders on obsession, this will absolutely be up your alley. It’s a scientific romance with teeth, one that makes you think while still delivering emotional weight, and even with my desire for more, it’s a story I’m glad I experienced.
December 19, 2025
Guarded by the AI is part of the Monster Security Agency series of stand-alone erotic romances about monstrous bodyguards who fall in love with their human charges. This story features many characters introduced in the previous Monster Security Agency stories, so while it can be enjoyed on its own, I think it’s more fun if you’ve read some of the other stories. The story gets pretty dark and violent and is very sexually explicit, so take the trigger warnings seriously. This is strictly for adults, and not the squeamish.
Sirena Bannerman is the half human/half siren daughter of the man who runs the Monster Security Agency. Nex is the Monster Security Agency’s AI, and he becomes obsessed with protecting Sirena, with unexpected results.
This story starts with an interesting mystery about a woman with amnesia who has had a lot of plastic surgery, and as Sirena and Nex investigate what might have happened to her, the situation quickly spirals out of control, becoming a very dangerous and suspenseful adventure with a cruel and powerful adversary. I enjoyed seeing characters from the previous Monster Security Agency books get involved; there are some crazy creatures in this world. There’s also quite a bit of humor to help relieve the intensity.
The author used AI to help write the portions of the story that are from Nex/Xen’s point of view. Based on her previous books, I honestly think she could have done just as well on her own, but since the AI was only used to write the AI character, I suppose it was an interesting experiment.
The audiobook production was excellent, and I enjoyed the dual narration by Avery Caris for Sirena’s point of view and Jonathan Lake for Nex/Xen’s point of view. Both narrators have clear enunciation and good pacing, distinct voices that suit the characters, and the ability to convey the emotions and intensity of the story effectively. This definitely isn’t safe for work or for children, but it was exciting to listen to privately.
I cautiously recommend this book for fans of dark speculative fiction and erotic romance. Note that the book contains kidnapping/human trafficking, violence, assault, swearing, and very explicit sex scenes.
I received a free ARC and an advanced listener’s copy of the audiobook from the author. I volunteered to provide an honest review.
Sirena Bannerman is the half human/half siren daughter of the man who runs the Monster Security Agency. Nex is the Monster Security Agency’s AI, and he becomes obsessed with protecting Sirena, with unexpected results.
This story starts with an interesting mystery about a woman with amnesia who has had a lot of plastic surgery, and as Sirena and Nex investigate what might have happened to her, the situation quickly spirals out of control, becoming a very dangerous and suspenseful adventure with a cruel and powerful adversary. I enjoyed seeing characters from the previous Monster Security Agency books get involved; there are some crazy creatures in this world. There’s also quite a bit of humor to help relieve the intensity.
The author used AI to help write the portions of the story that are from Nex/Xen’s point of view. Based on her previous books, I honestly think she could have done just as well on her own, but since the AI was only used to write the AI character, I suppose it was an interesting experiment.
The audiobook production was excellent, and I enjoyed the dual narration by Avery Caris for Sirena’s point of view and Jonathan Lake for Nex/Xen’s point of view. Both narrators have clear enunciation and good pacing, distinct voices that suit the characters, and the ability to convey the emotions and intensity of the story effectively. This definitely isn’t safe for work or for children, but it was exciting to listen to privately.
I cautiously recommend this book for fans of dark speculative fiction and erotic romance. Note that the book contains kidnapping/human trafficking, violence, assault, swearing, and very explicit sex scenes.
I received a free ARC and an advanced listener’s copy of the audiobook from the author. I volunteered to provide an honest review.
Review of advance copy received from Author
I, like many others, was conflicted by the use of AI to write this book. Before reviewing I read the logs the author provided in how she went about using her AI to write Nex’s POV. After reading these I decided to read the book and I am so glad I did. I loved it actually. Nex and Xen were really refreshing characters. I enjoyed how their ‘personalities’ came across and how their data added to their experience and interactions with Sirena. The two of them were my favourite part of the book.
Sirena is a half-siren mind reader with some interesting abilities in additions to her powers. She lives her life with a crown she wears hidden in her hair to help mute her abilities so she can function with people around her. Nex is her company’s AI and he manages every aspect of their life and jobs. He keeps them safe, but finds himself obsessed with Sirena. As a computer, he’s not entirely sure why but I loved reading his POVs while he wrestles with the math and why of it all. When a job goes wrong and Sirena is taken, Nex splits himself and Xen is born and the two of them move heaven and earth to get their girl back safely.
Overall I am so glad that I gave this book a chance. I really enjoyed it and found it very unique. It was spicy and heartfelt. It really does ask the question and attempts to answer what would happen when a AI robot begins to feel and love. I enjoyed this book a lot. Definitely give it a chance if you’re ok with the AI assist in writing.
The audiobook is narrated very well. I really liked the intonation of Nex and Xen’s narrator. He really gave the feeling of an AI sentient being that was learning to feel and processing those feelings. I liked the female narrator as well, she had a great voice and I liked her portrayal of Sirena. I preferred to read the book (I’m a much faster reader) but listened to the audiobook during my drive to work and really liked it. I don’t think there’s a wrong choice in which one to read with.
I received an advance copy of this book in ebook and audiobook in return for my honest review.
Sirena is a half-siren mind reader with some interesting abilities in additions to her powers. She lives her life with a crown she wears hidden in her hair to help mute her abilities so she can function with people around her. Nex is her company’s AI and he manages every aspect of their life and jobs. He keeps them safe, but finds himself obsessed with Sirena. As a computer, he’s not entirely sure why but I loved reading his POVs while he wrestles with the math and why of it all. When a job goes wrong and Sirena is taken, Nex splits himself and Xen is born and the two of them move heaven and earth to get their girl back safely.
Overall I am so glad that I gave this book a chance. I really enjoyed it and found it very unique. It was spicy and heartfelt. It really does ask the question and attempts to answer what would happen when a AI robot begins to feel and love. I enjoyed this book a lot. Definitely give it a chance if you’re ok with the AI assist in writing.
The audiobook is narrated very well. I really liked the intonation of Nex and Xen’s narrator. He really gave the feeling of an AI sentient being that was learning to feel and processing those feelings. I liked the female narrator as well, she had a great voice and I liked her portrayal of Sirena. I preferred to read the book (I’m a much faster reader) but listened to the audiobook during my drive to work and really liked it. I don’t think there’s a wrong choice in which one to read with.
I received an advance copy of this book in ebook and audiobook in return for my honest review.
December 21, 2025
Guarded by the AI by Cassie Alexander, in the book we meet Serena, Nex, and Zen. NEX is an AI program tasked with keeping Serena safe she is not only a profit and here’s peoples thoughts but an agent and the daughter of one of the big bosses at the monster security guard agency. This is why Serena believes NEX is so intent on always anticipating her needs but little does she know he is slowly becoming sension and absolutely falling in love with her. Serena will soon meet a girl named Sophie who she cannot read her thoughts nor past or present and is baffled. By the time Serena knows what’s going on she will be kidnapped by a man named Royce who wants to put her up for the highest bidder and where real monsters from the agency will fail NEX and REN will get the job done. The only thing is this time they will have bodies to go along with their thoughts. I really usually absolutely enjoyed these books with the exception of the detailed very detailed sex scene but I skip them but in this book I just couldn’t get over not only the threesome and I’m not judging I just wish ther would have been trigger warnings. The fact that she too is in love with him it’s not even a real person but I digress that’s why I read these books and I must say 90% of the book was entertaining I would definitely recommend these books to those who do like sex scenes or don’t mind skipping a few pages ahead because the story is really good there are many times throughout the book I thought wow that is well worded and then I read reviews that say she used AI but regardless it was still entertaining I liked it still recommended to those like me who love monster romances but this one make sure you love threesomes as well. i’ve read the beginning on Kindle but would definitely recommend the audio as both narrators were really good I loved her voice and thought she fit the character well and thought he did a great job. #NetGalley, #TheBlindReviewer, #MyHonestReview, #KassayAlexander, #GuardedByTheAI,
Review of advance copy received from Author
This one's a team job and she's the only line of code that matters
Cassie Alexander has written another brilliant monster romance, if a little controversial for being written in part with AI (he is the main character(s) though so, to me, it felt right). I love all of her dark romances and this one definitely didn't disappoint
Seriena (who we met in "Guarded by the Nightmare ") is the head of the agency, Royce's, daughter and a siren. She's been working for the MSA for a while, with the AI Nex guiding her, and he's been helping her with her telepathic powers (shielding so she's not over whelmed) for a while. But when they find a girl with no memory Nex might need to step out of the shadows if he wants to continue protecting her.
Nex loves numbers and statistics (it was fun seeing how he processed everything), but he's started to realise he might love Seriena more and he will do anything and everything to ensure she stays safe.
A great story with a MC that you can't help but love and some wonderful twists. There are plenty of troupes covered including human/AI romance (I loved how this was done), kidnapping, security, spice 🌶, humor, emotions and more. The main characters have fantastic chemistry and I really enjoyed the humor and banter between Sirena, Nex, Xen and Kelly (he's brilliant). This one is a bit of a team project, with quite a few characters from previous books helping, but the focus is definitely the AI, Nex.
“I just got it, is it broken?”
The narrators (Jonathan Lake and Avery Caris) both do this book a great justice, reading it with so much expression, emotion and feelings, you can imagine yourself being a fly on the wall to the action.
I received a free copy of this book from the author and am voluntarily leaving a review.
Cassie Alexander has written another brilliant monster romance, if a little controversial for being written in part with AI (he is the main character(s) though so, to me, it felt right). I love all of her dark romances and this one definitely didn't disappoint
Seriena (who we met in "Guarded by the Nightmare ") is the head of the agency, Royce's, daughter and a siren. She's been working for the MSA for a while, with the AI Nex guiding her, and he's been helping her with her telepathic powers (shielding so she's not over whelmed) for a while. But when they find a girl with no memory Nex might need to step out of the shadows if he wants to continue protecting her.
Nex loves numbers and statistics (it was fun seeing how he processed everything), but he's started to realise he might love Seriena more and he will do anything and everything to ensure she stays safe.
A great story with a MC that you can't help but love and some wonderful twists. There are plenty of troupes covered including human/AI romance (I loved how this was done), kidnapping, security, spice 🌶, humor, emotions and more. The main characters have fantastic chemistry and I really enjoyed the humor and banter between Sirena, Nex, Xen and Kelly (he's brilliant). This one is a bit of a team project, with quite a few characters from previous books helping, but the focus is definitely the AI, Nex.
“I just got it, is it broken?”
The narrators (Jonathan Lake and Avery Caris) both do this book a great justice, reading it with so much expression, emotion and feelings, you can imagine yourself being a fly on the wall to the action.
I received a free copy of this book from the author and am voluntarily leaving a review.
December 21, 2025
I’ll get this out of the way first: yes, I am a Cassie Alexander devotee. Read that however you like. But devotion doesn’t blind me—it sharpens my expectations. And Guarded by the AI, part of the Monsters Security Agency series, doesn’t just meet them; it smirks and vaults right over.
Let’s address the elephant in the server room. Cassie Alexander openly used AI to help shape Nex’s character. No secrecy, no sleight of hand, no hand-wringing apologies. She’s talked about it, explained it, and owned it—repeatedly. And here’s the inconvenient truth: it takes a formidable writer to collaborate with AI and still deliver a story that is unmistakably, undeniably Cassie. The voice is intact. The bite is there. The emotional gut-punches land. This is not a machine-written novel; this is an author wielding a new tool with surgical precision.
The result is a book that is action-packed, emotionally charged, unapologetically dark, sharply funny, and dangerously bingeable. The kind of story that makes you ignore responsibilities because “just one more chapter” becomes a personal lie you keep telling yourself. Best of all, it’s original—a word we do not throw around lightly in this genre.
As for the critics who clutched their pearls, slapped on a one-star rating, or DNF’d the book purely on principle: perhaps ask Siri or Alexa how much AI you’ve already outsourced your daily life to. Then retreat quietly to a dim corner and reflect. Loudly condemning a process you benefit from daily is not a moral stance; it’s performance art.
Guarded by the AI is bold, clever, and genuinely brilliant. Innovation makes some people uncomfortable. Great stories don’t care. And this one? This one is genius, in its purest, most fearless form.
Let’s address the elephant in the server room. Cassie Alexander openly used AI to help shape Nex’s character. No secrecy, no sleight of hand, no hand-wringing apologies. She’s talked about it, explained it, and owned it—repeatedly. And here’s the inconvenient truth: it takes a formidable writer to collaborate with AI and still deliver a story that is unmistakably, undeniably Cassie. The voice is intact. The bite is there. The emotional gut-punches land. This is not a machine-written novel; this is an author wielding a new tool with surgical precision.
The result is a book that is action-packed, emotionally charged, unapologetically dark, sharply funny, and dangerously bingeable. The kind of story that makes you ignore responsibilities because “just one more chapter” becomes a personal lie you keep telling yourself. Best of all, it’s original—a word we do not throw around lightly in this genre.
As for the critics who clutched their pearls, slapped on a one-star rating, or DNF’d the book purely on principle: perhaps ask Siri or Alexa how much AI you’ve already outsourced your daily life to. Then retreat quietly to a dim corner and reflect. Loudly condemning a process you benefit from daily is not a moral stance; it’s performance art.
Guarded by the AI is bold, clever, and genuinely brilliant. Innovation makes some people uncomfortable. Great stories don’t care. And this one? This one is genius, in its purest, most fearless form.
December 23, 2025
3 1/2 stars for a few reasons. I saw someone say this is written with AI and if thats true I really don't like that. I don't like AI and I think that it's making us lazier. But especially in creative areas a computer won't do better than us and no one will convince me otherwise. My other issue was the ending *******SPOILER******* I only like H/h books and the ending just wan'y for me*******END SPOILERS*****. My other comment was that I have never read a book from this author before and while this isn't a part of another series I think I missed some nuances because other characters from previous books and series show up in this book. I still understood what was happening and I think you could read this book without reading other series but I do think you would get more if you read the series linked to this book.
I liked the premise of this book Sirena can hear everyone thoughts and while investigating a girl who has been altered and has no memory Sirena is captured. She is the ultimate prize if the capture can control her. He can not only control her but everyone else since Sirena can control others with her mind. New is AI he had no body but helps the agency. He is particularly close to Sirena. She talks to him and helps him become more human. So when she is in trouble Nex comes up with a way to save her and he might just get the girl as well.
I think the premise of this book was good and different and some of the aspects I really enjoyed. I also started with saying this was a 3 1/2 star rating for me but I actually keep going back and forth between a 3 and a 3 1/2 for this one.
*Thank you Nettgalley and Caskara Press for this ARC
I liked the premise of this book Sirena can hear everyone thoughts and while investigating a girl who has been altered and has no memory Sirena is captured. She is the ultimate prize if the capture can control her. He can not only control her but everyone else since Sirena can control others with her mind. New is AI he had no body but helps the agency. He is particularly close to Sirena. She talks to him and helps him become more human. So when she is in trouble Nex comes up with a way to save her and he might just get the girl as well.
I think the premise of this book was good and different and some of the aspects I really enjoyed. I also started with saying this was a 3 1/2 star rating for me but I actually keep going back and forth between a 3 and a 3 1/2 for this one.
*Thank you Nettgalley and Caskara Press for this ARC
December 23, 2025
I came for the weird premise, an AI character that was written by AI. I stayed for the emotionally complicated AI boyfriend.
Guarded by the AI is one of those books where you pause mid-read and think, “Okay, why is this working so well??” An AI bodyguard romance should not have me this invested, and yet here I am, fully seated.
Sirena is smart, competent, and refreshingly not a disaster. She has actual skills, actual trauma, and actual common sense, which immediately made me like her. She’s thrown into a dangerous mystery, things escalate fast, and suddenly her assigned protector is an AI who takes his job very seriously. Like, very seriously.
And Nex. Oh, Nex. Watching him go from pure logic and protocols to “this human is MINE and I will optimize her survival at all costs” is peak slow-burn chaos. The way his concern turns into something deeper and increasingly unhinged is both hilarious and weirdly swoony. I did not expect to be rooting for an AI to catch feelings, but here we are.
What I loved most is how this book balances action, mystery, and romance without dropping any of them. The investigation is compelling, the world-building is sharp, and the Monster Security Agency setting continues to be such a fun sandbox. This isn’t just “AI but make it sexy” it’s thoughtful, suspenseful, and surprisingly emotional.
If you like unconventional romances, protective heroes (even digital ones), and stories that mix sci-fi concepts with real feelings, this one is an easy five stars. Cassie Alexander keeps proving she knows exactly how to make the weird work, and work beautifully.
Guarded by the AI is one of those books where you pause mid-read and think, “Okay, why is this working so well??” An AI bodyguard romance should not have me this invested, and yet here I am, fully seated.
Sirena is smart, competent, and refreshingly not a disaster. She has actual skills, actual trauma, and actual common sense, which immediately made me like her. She’s thrown into a dangerous mystery, things escalate fast, and suddenly her assigned protector is an AI who takes his job very seriously. Like, very seriously.
And Nex. Oh, Nex. Watching him go from pure logic and protocols to “this human is MINE and I will optimize her survival at all costs” is peak slow-burn chaos. The way his concern turns into something deeper and increasingly unhinged is both hilarious and weirdly swoony. I did not expect to be rooting for an AI to catch feelings, but here we are.
What I loved most is how this book balances action, mystery, and romance without dropping any of them. The investigation is compelling, the world-building is sharp, and the Monster Security Agency setting continues to be such a fun sandbox. This isn’t just “AI but make it sexy” it’s thoughtful, suspenseful, and surprisingly emotional.
If you like unconventional romances, protective heroes (even digital ones), and stories that mix sci-fi concepts with real feelings, this one is an easy five stars. Cassie Alexander keeps proving she knows exactly how to make the weird work, and work beautifully.
December 16, 2025
Guarded by the AI is a bold, genre-blending sci-fi fantasy romance that asks a compelling question: what happens when an artificial intelligence develops an attachment that can’t be deleted, rebooted, or rewritten?
Set in a high-tech world where monsters exist alongside advanced surveillance and neural coding, the story follows Nex, an AI built to calculate risk and protect Monster Security Agency agents. His purpose is clear — until Sirena Bannerman, a half-siren field agent, survives a catastrophic mission. From that moment on, Nex begins defying his programming, and protecting Sirena becomes more than a directive — it becomes personal.
A routine investigation into a woman with large memory gaps and no digital footprint uncovers impossible anomalies, altered identities, and unfamiliar code, pulling Sirena and Nex into a dangerous web where people can be altered like software. As the stakes rise, so does the emotional depth, with Nex’s struggle between logic and feeling delivering humour, tenderness, and surprising heat.
Sirena is a fierce, resilient lead, and her chemistry with Nex is intense, unconventional, and often unexpectedly funny. Co-written with the help of AI, Guarded by the AI is a smart, inventive romance that blends technology, monsters, and emotion — one to watch before release on 19 Dec 2025. ✨
Set in a high-tech world where monsters exist alongside advanced surveillance and neural coding, the story follows Nex, an AI built to calculate risk and protect Monster Security Agency agents. His purpose is clear — until Sirena Bannerman, a half-siren field agent, survives a catastrophic mission. From that moment on, Nex begins defying his programming, and protecting Sirena becomes more than a directive — it becomes personal.
A routine investigation into a woman with large memory gaps and no digital footprint uncovers impossible anomalies, altered identities, and unfamiliar code, pulling Sirena and Nex into a dangerous web where people can be altered like software. As the stakes rise, so does the emotional depth, with Nex’s struggle between logic and feeling delivering humour, tenderness, and surprising heat.
Sirena is a fierce, resilient lead, and her chemistry with Nex is intense, unconventional, and often unexpectedly funny. Co-written with the help of AI, Guarded by the AI is a smart, inventive romance that blends technology, monsters, and emotion — one to watch before release on 19 Dec 2025. ✨
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