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The First Sinner: A Dark Why Choose Stepbrother Cult Novella
Some girls outgrow their sins.
Lorelei Becerra only learns new ones.
Three years in the Vale family taught Lorelei one don’t touch what isn’t yours.
Especially not Ash Vale—her arrogant, possessive stepbrother.
Especially not his best friend Rafe, who looks at her like he already knows how she tastes.
But summer at the Vale estate changes everything.
A midnight swim.
A forbidden kiss.
And suddenly, the rules that kept her safe are ash.
Because Ash is always watching.
Rafe is waiting for her.
And the Sanctum—the secretive, velvet-draped cult her family serves—has been preparing her for far longer than she realized.
One kiss ruins her.
One touch brands her.
And one prophecy will claim her.
She was never meant to be saved.
She was meant to burn.
Lorelei Becerra only learns new ones.
Three years in the Vale family taught Lorelei one don’t touch what isn’t yours.
Especially not Ash Vale—her arrogant, possessive stepbrother.
Especially not his best friend Rafe, who looks at her like he already knows how she tastes.
But summer at the Vale estate changes everything.
A midnight swim.
A forbidden kiss.
And suddenly, the rules that kept her safe are ash.
Because Ash is always watching.
Rafe is waiting for her.
And the Sanctum—the secretive, velvet-draped cult her family serves—has been preparing her for far longer than she realized.
One kiss ruins her.
One touch brands her.
And one prophecy will claim her.
She was never meant to be saved.
She was meant to burn.
114 pages, Kindle Edition
Published August 8, 2025
10 people are currently reading
11 people want to read
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Displaying 1 - 25 of 25 reviews
November 10, 2025
I received an ARC copy of this book for an honest review.
3.85 ⭐️
The story picked up 3 years later. Lorelei still didn’t know what happened. I love that we saw more of Rafe and Ash! I’m curious to what’s happening. I know more questions will be answered in the upcoming books. Can’t wait for the next release.
3.85 ⭐️
The story picked up 3 years later. Lorelei still didn’t know what happened. I love that we saw more of Rafe and Ash! I’m curious to what’s happening. I know more questions will be answered in the upcoming books. Can’t wait for the next release.
August 16, 2025
The First Sinner is a brilliantly written dark romance that instantly captured my attention—especially after seeing the long list of trigger warnings (which, let’s be honest, made me even more curious). This stepbrother, why-choose romance pulls you into the twisted world of Lorelei (Lark), her stepbrothers Asher and Cassian, their best friend Raphael (Rafe), and even Asher’s girlfriend, Talia—yes, this harem is that deliciously complicated.
(WARNING NEXT PART MAY CONTAIN SOME SPOILERS!! YOU WERE WARNED:::::
Set within a sinister cult called The Sanctum, the story revolves around a prophecy in which Lorelei may be the perfect vessel. Much of the plot keeps her (and the reader) in the dark about her true role, creating an eerie tension that runs throughout. The themes here are unapologetically dark—taboo relationships, obsession, manipulation, control, and even coercion.
Despite its brevity, the storytelling is gripping and immersive. Honestly, this short story could easily have been expanded into a full-length novel with how rich the world-building and plot are. I especially loved watching Lorelei evolve—she begins powerless and unaware, yet grows into her strength, claiming her life and her power in a way that’s both satisfying and empowering.
The chemistry between the characters is beyond steamy, with a spice level I’d rate at 4/5. The interactions between the boys—and with Lorelei—were written so well that I found myself not wanting the book to end. My only true disappointment is that it was so short; I wanted more time in this dark, addictive world.
If you’re a fan of taboo, twisted, and passionate dark romances, do yourself a favor and pick this one up. I, for one, cannot wait to see what Jus Synn and Kamila Garza bring us next.
(WARNING NEXT PART MAY CONTAIN SOME SPOILERS!! YOU WERE WARNED:::::
Set within a sinister cult called The Sanctum, the story revolves around a prophecy in which Lorelei may be the perfect vessel. Much of the plot keeps her (and the reader) in the dark about her true role, creating an eerie tension that runs throughout. The themes here are unapologetically dark—taboo relationships, obsession, manipulation, control, and even coercion.
Despite its brevity, the storytelling is gripping and immersive. Honestly, this short story could easily have been expanded into a full-length novel with how rich the world-building and plot are. I especially loved watching Lorelei evolve—she begins powerless and unaware, yet grows into her strength, claiming her life and her power in a way that’s both satisfying and empowering.
The chemistry between the characters is beyond steamy, with a spice level I’d rate at 4/5. The interactions between the boys—and with Lorelei—were written so well that I found myself not wanting the book to end. My only true disappointment is that it was so short; I wanted more time in this dark, addictive world.
If you’re a fan of taboo, twisted, and passionate dark romances, do yourself a favor and pick this one up. I, for one, cannot wait to see what Jus Synn and Kamila Garza bring us next.
August 11, 2025
The First Sinner is the first book (excluding the prequel) in Synn and Garza's The Step Sins. This is a dark, why choose, stepbrother, cult novella. While the story is really about Lorelei (aka Lark), there is a small yet key cast of characters including her stepbrothers, Cassian and Asher, Asher's best friend Raphael (Rafe), and Asher's girlfriend, Talia. It seems all are members of a cult, The Sanctum, and there is a prophecy. Lorelei may be The Vessel, but she doesn't have a full picture of what is to come, and no one is allowed to tell her.
The men all seem to worship Lorelei, and want more. Lorelei starts off accepting their attention and ministrations, and enjoying it, but then a beautiful thing happens. Lorelei steps into her power and takes control.
The writing is dark, rife with obsession, control, coercion and more. There is significant sexual content, individual, duos and groups, there is psychological manipulation, forced ritual participation, and more. You must check out the trigger warnings before delving in. That said, if you determine that your mental health will not suffer or be triggered, dive in. The writing is sinfully delicious. My main complaint is that this is a novella. I would love a full length novel with these characters, further exploring their relationships, their sizzling chemistry, and more details about this cult.
I'm not sure how many installments are planned for this series but coming next is The First Flame and I will definitely be keeping an eye out for it.
The men all seem to worship Lorelei, and want more. Lorelei starts off accepting their attention and ministrations, and enjoying it, but then a beautiful thing happens. Lorelei steps into her power and takes control.
The writing is dark, rife with obsession, control, coercion and more. There is significant sexual content, individual, duos and groups, there is psychological manipulation, forced ritual participation, and more. You must check out the trigger warnings before delving in. That said, if you determine that your mental health will not suffer or be triggered, dive in. The writing is sinfully delicious. My main complaint is that this is a novella. I would love a full length novel with these characters, further exploring their relationships, their sizzling chemistry, and more details about this cult.
I'm not sure how many installments are planned for this series but coming next is The First Flame and I will definitely be keeping an eye out for it.
August 10, 2025
This book seriously pulled me in from the very first page. It picks up three years later, and wow! Things get intense fast. I loved seeing more of Rafe in this one. He’s dark, complicated, and completely addictive. Ash, Rafe, Cassian, and Talia all brought something unique to the table, and the dynamic between them kept things deliciously tense.
But Lorelei? She completely stole the show. She’s not just the “vessel” anymore, she’s taking control and owning every bit of her power. And honestly? Watching three men basically worship her like she’s the center of their world was everything. It was dark, twisted, and so, so satisfying.
The story had me hooked the whole way through, but I do wish it was longer. The ending felt like it came too fast, and now I’m counting down the days until the next one releases. I need more answers. I need more chaos. I just… need more.
And while Rafe definitely shined this time around, I’m still a Cassian girl, through and through.
If you’re into dark romance with taboo vibes, cult twists, obsession, and insane chemistry, this novella is 100% worth the read. And the spice level? Absolutely off the charts.
But Lorelei? She completely stole the show. She’s not just the “vessel” anymore, she’s taking control and owning every bit of her power. And honestly? Watching three men basically worship her like she’s the center of their world was everything. It was dark, twisted, and so, so satisfying.
The story had me hooked the whole way through, but I do wish it was longer. The ending felt like it came too fast, and now I’m counting down the days until the next one releases. I need more answers. I need more chaos. I just… need more.
And while Rafe definitely shined this time around, I’m still a Cassian girl, through and through.
If you’re into dark romance with taboo vibes, cult twists, obsession, and insane chemistry, this novella is 100% worth the read. And the spice level? Absolutely off the charts.
August 8, 2025
⚠️Check TW’s before reading⚠️
🖤 You must read the prequel (The First Touch) as this book picks up right after that 3 year jump at the end of book 1.
🖤 Umm where do I even start?! 10/10, I need the second book out now!! The boys!!! God that first scene where Ash kisses Rafe had me giggling and kicking my feet. Oh and don’t get me started on when she dominated them! I love a good pegging scene and that scene delivered. God, the pan panic is real cause why are they all so hot! Throughout the story you see how Lorelei is still kept in the dark from a lot of things and everyone is keeping things from each other, but slowly she’s finding out more about what it all means. At times, I found myself just as confused as Lorelei but slowly my questions were answered and things are revealed, not enough to give it all away at once but just enough to keep you on your toes and wanting more.
📚Book Type: book2 in The Step-Sins series
🖤Primarily FMM
💚Religious cult vibes
🖤Pegging
💚Step sibling entanglement
🖤Exhibitionism
💚Drug and alcohol use
And more!
🖤 You must read the prequel (The First Touch) as this book picks up right after that 3 year jump at the end of book 1.
🖤 Umm where do I even start?! 10/10, I need the second book out now!! The boys!!! God that first scene where Ash kisses Rafe had me giggling and kicking my feet. Oh and don’t get me started on when she dominated them! I love a good pegging scene and that scene delivered. God, the pan panic is real cause why are they all so hot! Throughout the story you see how Lorelei is still kept in the dark from a lot of things and everyone is keeping things from each other, but slowly she’s finding out more about what it all means. At times, I found myself just as confused as Lorelei but slowly my questions were answered and things are revealed, not enough to give it all away at once but just enough to keep you on your toes and wanting more.
📚Book Type: book2 in The Step-Sins series
🖤Primarily FMM
💚Religious cult vibes
🖤Pegging
💚Step sibling entanglement
🖤Exhibitionism
💚Drug and alcohol use
And more!
August 8, 2025
This book is a dark, taboo cult story featuring the FMC, Lorellai (Lark), her stepbrothers, and the rest of their crazy cultish family.
The book is written somewhat like poetry - which is absolutely beautiful but made it hard for me to tell what was going on at times. The characters are keeping secrets from each other, and Lorrelai is mostly in the dark - she knows she's promised to an important role in her family's cult (as the Vessel), but she doesn't know what that means, and she's kept in the dark at times. This story picks up 3 years after the prequel, but Lorrelai is still bound to her stepbrothers and the cult.
I enjoyed seeing more of all of the characters - Rafe and Ash are central in this book, while Cassian is a leader but we see less of him here. The story immerses you in a world dripping in sin and debauchery - think drugs, parties, sex, and the idolization of all things sinful.
This is definitely a suspenseful book - I can't wait for the next book in the series!
The book is written somewhat like poetry - which is absolutely beautiful but made it hard for me to tell what was going on at times. The characters are keeping secrets from each other, and Lorrelai is mostly in the dark - she knows she's promised to an important role in her family's cult (as the Vessel), but she doesn't know what that means, and she's kept in the dark at times. This story picks up 3 years after the prequel, but Lorrelai is still bound to her stepbrothers and the cult.
I enjoyed seeing more of all of the characters - Rafe and Ash are central in this book, while Cassian is a leader but we see less of him here. The story immerses you in a world dripping in sin and debauchery - think drugs, parties, sex, and the idolization of all things sinful.
This is definitely a suspenseful book - I can't wait for the next book in the series!
August 14, 2025
⭐⭐⭐⭐
🌶️🌶️🌶️🌶️
The First Sinner chants in the same poetic undertone as The First Touch. Smooth, rich and dark. Everything is related in the most expressive singular way, it stirs something in me, it moves me. I will confess, I am very much hung up on the way these ladies write.
The story is once more decadent. A cult, a prophecy, a ritual. There's no salvation for the Vessel and three men obsessed with her, may as well just gave in to temptation. And oh, do they? Hahaha
The tension is mental - in a good way. So well-crafted, I am still trying to calm the butterflies in my belly.
The characters, well, Ash and Rafe that is all I am gonna say. I am here for them. Those two have left their mark in me. Chapter 14 is what wet dreams are made of.
The First Touch was the loss of innocence. The First Sinner was the loss of inhibition. I wonder what The First Flame will bring. Can't wait.
🌶️🌶️🌶️🌶️
The First Sinner chants in the same poetic undertone as The First Touch. Smooth, rich and dark. Everything is related in the most expressive singular way, it stirs something in me, it moves me. I will confess, I am very much hung up on the way these ladies write.
The story is once more decadent. A cult, a prophecy, a ritual. There's no salvation for the Vessel and three men obsessed with her, may as well just gave in to temptation. And oh, do they? Hahaha
The tension is mental - in a good way. So well-crafted, I am still trying to calm the butterflies in my belly.
The characters, well, Ash and Rafe that is all I am gonna say. I am here for them. Those two have left their mark in me. Chapter 14 is what wet dreams are made of.
The First Touch was the loss of innocence. The First Sinner was the loss of inhibition. I wonder what The First Flame will bring. Can't wait.
August 12, 2025
This steamy, dark, taboo keeps you on your toes through and through!
The first book in the Step Sins Series (aside from the prequel) is so suspenseful! I always love relating to or feeling a characters emotions in a story, and in this, when it comes to the secrets and the romance, I feel just like Lorelei. We get a lot of Rafe and Ash in The First Sinner, even with some MM which was amazing. The prequel had me excited for their dynamic in this story. Although we have less Cassian, his presence is still so huge! Lorelei is left in the dark, and while some things are uncovered, there is still a lot more to know. I can't wait for the next story, The First Flame! If you enjoy dark short stories, then this series is a must read.
The first book in the Step Sins Series (aside from the prequel) is so suspenseful! I always love relating to or feeling a characters emotions in a story, and in this, when it comes to the secrets and the romance, I feel just like Lorelei. We get a lot of Rafe and Ash in The First Sinner, even with some MM which was amazing. The prequel had me excited for their dynamic in this story. Although we have less Cassian, his presence is still so huge! Lorelei is left in the dark, and while some things are uncovered, there is still a lot more to know. I can't wait for the next story, The First Flame! If you enjoy dark short stories, then this series is a must read.
August 12, 2025
This was the best way to follow up after The First Touch. Baby this novella maybe short but it comes in with a bang. There was just one rule Don’t touch wasn’t isn’t yours. Chile that went out the window for Lorelei, Ash and adding in his best friend Rafe starts to get into an entanglement. The tension was magnetic and the spicy omggg how do I even rate it because it broke the meter for me. These girls know how to do it right because not only was their smut but their was plot and the pacing kept me turning pages like out was running out of oxygen. If you love taboo romance, morally grey men, and add a good why choose. This is it!
August 2, 2025
These authors are back again picking up with Lorelei’s story. I loved seeing more of Rafe in this one. This novella started with a bang and continued throughout the whole book.
The characters and storyline kept me intrigued the whole way. I enjoyed Ash, Rafe, Cassian, and Talia. The ending came so soon and has me waiting “patiently” for the next book in the series.
I’m ready to see what happens next and what’s in store for Lorelei and the other characters.
The characters and storyline kept me intrigued the whole way. I enjoyed Ash, Rafe, Cassian, and Talia. The ending came so soon and has me waiting “patiently” for the next book in the series.
I’m ready to see what happens next and what’s in store for Lorelei and the other characters.
August 9, 2025
This is the second book in the series you gonna have to read the prequel in the series. We are back just 3 years ahead in the future. This is a taboo steamy book we have Lorelei, Ash, and Rafe and it never been more steamy then ever. The tropes in this book is wow we have pegging (wow) Drugs, Step siblings, and many more. Cant wait to see what the series has in store for me, Make sure to check out the book.
August 9, 2025
A Hot & Sinful War for HER
This book is hot, dark, bl00dy, and eager to leave you begging for a taste. Lorelei is the Vessel, the prize, the need they all want. Cassian, Ash, Rafe, and even Talia know the power she yields and will stop at nothing to get her even if that means dueling amongst themselves. MM interactions, exhibitionism, and bl00dy ritualistic “behavior” are just the tip of the iceberg. You don’t want to miss this series! I can’t wait for the next one!!
This book is hot, dark, bl00dy, and eager to leave you begging for a taste. Lorelei is the Vessel, the prize, the need they all want. Cassian, Ash, Rafe, and even Talia know the power she yields and will stop at nothing to get her even if that means dueling amongst themselves. MM interactions, exhibitionism, and bl00dy ritualistic “behavior” are just the tip of the iceberg. You don’t want to miss this series! I can’t wait for the next one!!
August 12, 2025
Hooked right away! Get more of the rest of the guys in this book then the prequel we get a little more of Asher and Rafe. But 3 men after 1 girl Lorelei they worship the ground she walks on. Lorelei is a new to being a sinner and she is not letting anything coming in her way! This takes us 3 years after the prequel there is obsession, ritualized sexuality coercion and more this book is also taboo. Check for triggers before reading this. This is a dark romance/cult thriller.
November 11, 2025
This book is so messed up and I love it. It's based around lorelai and her step brothers cassian and ash who are part of a cult that worships the flame cassia believes that Lorelai is the flame they're spent years grooming her plotting different points. It would seem ash and rage want to get her out of the cult but cassian wants her firmly In The middle ... so what happens when the burns.
I received a free copy of this book via Booksprout and am voluntarily leaving a review.
I received a free copy of this book via Booksprout and am voluntarily leaving a review.
December 11, 2025
"Now, you are more than just flesh. You're the vessel-made to be filled, to be remade, to be worshipped in ruin."
This series is spicing up with every book. I love when I have a lot of love interest choices *smirking so hard right now*
If you like:
🖤 Dark romance
🖤 Step-sibling entanglements
🖤 Religious cult vibes
🖤 Forbidden
🖤 Exh!bition activities
🖤 FMM Encounter
🖤 Trauma and drama 🫠😅
🖤 Obsessive tendencies
This book has all of this and more 😮💨
This series is spicing up with every book. I love when I have a lot of love interest choices *smirking so hard right now*
If you like:
🖤 Dark romance
🖤 Step-sibling entanglements
🖤 Religious cult vibes
🖤 Forbidden
🖤 Exh!bition activities
🖤 FMM Encounter
🖤 Trauma and drama 🫠😅
🖤 Obsessive tendencies
This book has all of this and more 😮💨
August 5, 2025
How do I find the words for this??? Exquisite, a masterpiece, exhilarating, beautiful, tormented, jaw dropping, sensual, soul crushing…all fit in their own ways. This book will leave you begging for more but also questioning your life choices in the same breath. It’s everything a dark romance with all the tropes in it. Pick up this book asap and devour it like it does you!!!
August 8, 2025
Wow! I am a new reader to these authors and I am tearing up their books! I can’t read them fast enough and they always leave me wanting more! When is the next one coming out? lol it’s spicy and a bit sassy I am loving the character development through their dialogues and interactions . Can’t wait to see what happens next in this series.
August 16, 2025
This was intense, but oh, so good! I loved the prequel, and I loved this one.
I was clapping my hands when Lorelei came into her own. I was so unbelievably proud!!
This book is dark and twisted, but it reels you in and won't let you go until it spits you out.
I will not give anything anyway, but once you start this, prepare to get no sleep. lol
I was clapping my hands when Lorelei came into her own. I was so unbelievably proud!!
This book is dark and twisted, but it reels you in and won't let you go until it spits you out.
I will not give anything anyway, but once you start this, prepare to get no sleep. lol
August 22, 2025
Deliciousness increased. Ten fold like UGHHHHHHH. Now I love Rafe as much as Cassian and Ash - I also loved our FMC Lorelei (Lark) - she turns into a bad a$$. She learns the truth about the brothers and I think we expected her to cower an run but no baby she is handling it with grace. And it’s already made her SO much stronger.
November 17, 2025
This is book 2 of The Step Sins series. Please watch your triggers.
The characters continue to compel and were chaotic and complex. Plot continues to expand and world building continues to impress. Recommend.
Grab a copy, kick back and enjoy!.
I received a free copy of this book via Booksprout and am voluntarily leaving a review.
The characters continue to compel and were chaotic and complex. Plot continues to expand and world building continues to impress. Recommend.
Grab a copy, kick back and enjoy!.
I received a free copy of this book via Booksprout and am voluntarily leaving a review.
December 2, 2025
“For those who don’t pray anymore, only worship the one who promised to burn it all down.” Love this dedication
The story picked up 3 years later. After the prequel, Lorelei still didn’t know what happened.
This is a steamy, taboo, suspenseful, why choose, dark, step brother cult novella. It’s captivates your attention and keeps you on your toes.
The story picked up 3 years later. After the prequel, Lorelei still didn’t know what happened.
This is a steamy, taboo, suspenseful, why choose, dark, step brother cult novella. It’s captivates your attention and keeps you on your toes.
August 5, 2025
Deliciously dark and spicy. Love that Lorelei is not just excepting that she is the vessel, she is owning it, and using it to her full advantage. Why not? 3 men to worship her like she is the most holy thing in the world. Yes, PLEASE!!!!!
August 15, 2025
I love how I was able to get easily lost in this book like the other. The pull was real with this book and the essence it brings to the world. I love this book as much as it prequel ( or maybe a little more). I also fall in love with this author and she is now going into my favorite group.
August 16, 2025
I jumped right in as soon as I finished the first touch , I freaking love it , it had me glued to my seat from the very beginning…
August 19, 2025
Wow I need more. My thrist was not satisfied. This storyline hooks you like nothing before. I can't wait for book 2.
Displaying 1 - 25 of 25 reviews