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Forbidden Variables
Some things are predictable.
Measured.
Contained.
Understood.
This isn’t one of them.
Ana and James weren’t looking for anything.
They already had everything they were supposed to want — careers, families, lives carefully built over years.
Then one delayed flight changes everything.
What begins as instant chemistry becomes something far more a connection neither of them can explain or ignore. Drawn together by sharp wit, late-night conversations, music, and the terrifying feeling of being truly seen, they find themselves crossing lines they never thought they would approach.
Because some things refuse to stay rational.
Not the pull between them.
Not the way they understand each other without trying.
Not how quickly it becomes impossible to walk away.
It isn’t simple.
It isn’t right.
And it may cost them everything.
But sometimes the things you’re meant to resist are the very things that make you feel alive again.
Measured.
Contained.
Understood.
This isn’t one of them.
Ana and James weren’t looking for anything.
They already had everything they were supposed to want — careers, families, lives carefully built over years.
Then one delayed flight changes everything.
What begins as instant chemistry becomes something far more a connection neither of them can explain or ignore. Drawn together by sharp wit, late-night conversations, music, and the terrifying feeling of being truly seen, they find themselves crossing lines they never thought they would approach.
Because some things refuse to stay rational.
Not the pull between them.
Not the way they understand each other without trying.
Not how quickly it becomes impossible to walk away.
It isn’t simple.
It isn’t right.
And it may cost them everything.
But sometimes the things you’re meant to resist are the very things that make you feel alive again.
279 pages, Kindle Edition
Published June 23, 2026
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Displaying 1 - 9 of 9 reviews
June 23, 2026
I didn’t expect to love this messy story as much as I did. I was giggling and kicking my feet one second and then crying the next. It just hit me in the feels and I absolutely devoured this book.
I love how it shows how messy life can be. How we settle into routines and just let life pass along without actually living it. I did not expect to root for the cheaters, but they had me from the moment they met.
Absolutely worth reading if you want a romance with adult characters with life experiences making morally messy life choices. Ana and James were both very likeable characters and you will end up rooting for them even when it’s morally wrong.
I love how it shows how messy life can be. How we settle into routines and just let life pass along without actually living it. I did not expect to root for the cheaters, but they had me from the moment they met.
Absolutely worth reading if you want a romance with adult characters with life experiences making morally messy life choices. Ana and James were both very likeable characters and you will end up rooting for them even when it’s morally wrong.
June 23, 2026
This is the book I've been waiting for to cure my book slump. I was getting fed up of reading books that overuse descriptions and similes like their readers and their life depend on it. (See what I did there?)
This book is intelligent, witty, and well paced. It has just the right balance of humour, spice, yearning and dealing with past trauma without going over the top or overdoing any of it.
The spark between the main characters was spot on from the start and as someone who has lived both sides of the MCs respective marriages. I get it. All of it.
The correlation of the storyline and the analogy of the bacterial growth curve was chef's kiss. It was woven into the story progression in a clever way.
I will definitely be revisiting this book in the future.
This book is intelligent, witty, and well paced. It has just the right balance of humour, spice, yearning and dealing with past trauma without going over the top or overdoing any of it.
The spark between the main characters was spot on from the start and as someone who has lived both sides of the MCs respective marriages. I get it. All of it.
The correlation of the storyline and the analogy of the bacterial growth curve was chef's kiss. It was woven into the story progression in a clever way.
I will definitely be revisiting this book in the future.
June 23, 2026
She's done it again! 🤌🏻🖤
Another incredible book by S.B. Vale! This came out today and I downloaded it as soon as I woke up 1. Because of the hype from her ARC readers and SB herself and 2. Because of how much I enjoyed her other work and I have struggled to put it down all day! The thought she has clearly put into this book is insane, without giving anything away, there's some clever stuff in here! I'm genuinely in awe of her as an author and I cannot wait to read all of her future work.
As usual, check your triggers but I highly recommend reading 🖤
Another incredible book by S.B. Vale! This came out today and I downloaded it as soon as I woke up 1. Because of the hype from her ARC readers and SB herself and 2. Because of how much I enjoyed her other work and I have struggled to put it down all day! The thought she has clearly put into this book is insane, without giving anything away, there's some clever stuff in here! I'm genuinely in awe of her as an author and I cannot wait to read all of her future work.
As usual, check your triggers but I highly recommend reading 🖤
Review of advance copy received from Author
Morally messy, forbidden love, yearning and boundaries that shouldn’t be crossed. Although you do start to doubt that last part.
This book is about 2 scientist that meet at an airport. Instant chemistry. The universe puts them together again and again turning the instant chemistry into a connection neither of them wanted. Not because they don’t want love. But because they were supposed to have already found their happily ever after.
This book is about life. Its raw and seldom easy and clean. Its about marriages slowly turning into joined calendars and boiler appointments. About feeling like somewhere along the way you became a habit. A convenience. Something that was there all along. Until someone comes along that shows you what its like to be seen again.
This book surprised me a lot. Mostly because I would never in a million years thought I would be rooting for two married people to get together. Its definitely morally messy! I loved the characters. I fell in love with Ana and James and I felt for them. And I hated Mark with a passion. All i can say is "Mothersday".. Really?
This book is so much more than just a book about two people cheating. Its emotional, full of curveballs and real life situations. Its mature, funny but also emotionally layered.
This is the second book I have read by this author. The first being FAFO. And I loved both but this one did go to the number one spot for me.
This book does contain spice and also check your triggers. On a scale from 1-10 I gave this a 9!
This book is about 2 scientist that meet at an airport. Instant chemistry. The universe puts them together again and again turning the instant chemistry into a connection neither of them wanted. Not because they don’t want love. But because they were supposed to have already found their happily ever after.
This book is about life. Its raw and seldom easy and clean. Its about marriages slowly turning into joined calendars and boiler appointments. About feeling like somewhere along the way you became a habit. A convenience. Something that was there all along. Until someone comes along that shows you what its like to be seen again.
This book surprised me a lot. Mostly because I would never in a million years thought I would be rooting for two married people to get together. Its definitely morally messy! I loved the characters. I fell in love with Ana and James and I felt for them. And I hated Mark with a passion. All i can say is "Mothersday".. Really?
This book is so much more than just a book about two people cheating. Its emotional, full of curveballs and real life situations. Its mature, funny but also emotionally layered.
This is the second book I have read by this author. The first being FAFO. And I loved both but this one did go to the number one spot for me.
This book does contain spice and also check your triggers. On a scale from 1-10 I gave this a 9!
July 13, 2026
I read this book in two sittings because I was desperate to know whether there would be a happily ever after for the main characters or not.
Forbidden Variables was such an easy read due to it being so well written. I really enjoyed the humour, the science, and the music references (the playlist and knitting pattern were such a lush touch), as well as the storyline and characters.
I felt for the main characters and the tough decisions and situations they faced.
This book shows that life can be messy and full of curveballs - The loneliness that can easily occur in a marriage was portrayed brilliantly, as were other topics that can be difficult to discuss.
S.B. Vale is a fantastic writer who really brought the story and the characters to life in the most beautiful way.
100% recommend and can't wait to see what she does next!
Forbidden Variables was such an easy read due to it being so well written. I really enjoyed the humour, the science, and the music references (the playlist and knitting pattern were such a lush touch), as well as the storyline and characters.
I felt for the main characters and the tough decisions and situations they faced.
This book shows that life can be messy and full of curveballs - The loneliness that can easily occur in a marriage was portrayed brilliantly, as were other topics that can be difficult to discuss.
S.B. Vale is a fantastic writer who really brought the story and the characters to life in the most beautiful way.
100% recommend and can't wait to see what she does next!
Review of advance copy received from Author
This book captivated me right away, and I held on the for the entire ride. 😉
The plot had me so impressed, and completely invested. I laughed out loud from chapter one and all through. The banter had me blushing hard, and the tension 🥵 had me gripping my phone until 2 am. I needed to know what happend.
Two characters meet in an airport where drinks flow, and turbulence makes for one intesne bumpy ride. This slow burn romance had some intensity off the plane than on it, and I was not prepared. This story was such an easy read, and I enjoyed every second. ♥️ can't wait for more from this author!
If you love:
We shouldn't be doing this
Cheating trope (done right)
He falls first
Spicy ❤️🔥
Sloooooow burn
This is for YOU 😘
The plot had me so impressed, and completely invested. I laughed out loud from chapter one and all through. The banter had me blushing hard, and the tension 🥵 had me gripping my phone until 2 am. I needed to know what happend.
Two characters meet in an airport where drinks flow, and turbulence makes for one intesne bumpy ride. This slow burn romance had some intensity off the plane than on it, and I was not prepared. This story was such an easy read, and I enjoyed every second. ♥️ can't wait for more from this author!
If you love:
We shouldn't be doing this
Cheating trope (done right)
He falls first
Spicy ❤️🔥
Sloooooow burn
This is for YOU 😘
Review of advance copy received from Author
This book felt like such a wild card - I was not expecting to feel the way I did, especially so early on on the book.
S.B has a unique way of telling a story that has you completely immersed and ends up making you question your morals.
The yearning in this book was some of the best I've ever read, the structure and pacing of the writing only added to the gut achingly raw desolation.
I loved that the author stayed true to real human emotion and circumstance, it's messy and it's immoral, but why did it feel so right?
I will forever rave about this book, if you're looking for a book that will set your compass spinning and have you questioning what you thought was right - THIS IS IT!
S.B has a unique way of telling a story that has you completely immersed and ends up making you question your morals.
The yearning in this book was some of the best I've ever read, the structure and pacing of the writing only added to the gut achingly raw desolation.
I loved that the author stayed true to real human emotion and circumstance, it's messy and it's immoral, but why did it feel so right?
I will forever rave about this book, if you're looking for a book that will set your compass spinning and have you questioning what you thought was right - THIS IS IT!
Review of advance copy received from Author
This book really took me by surprise as the main plot is something I said I wouldn't be interested in. Well I certainly got proven wrong on that one.
After meeting at an airport the chemistry between the leading characters is undeniable, however they are both married and know they absolutely shouldn't want what is so glaringly obvious to them. The yearning and the sexual tension between these two is off the charts and I could not put it down.
Absolutely a five star read for me and I look forward to reading more from the author.
After meeting at an airport the chemistry between the leading characters is undeniable, however they are both married and know they absolutely shouldn't want what is so glaringly obvious to them. The yearning and the sexual tension between these two is off the charts and I could not put it down.
Absolutely a five star read for me and I look forward to reading more from the author.
July 10, 2026
I did not think I would be rooting for the cheaters but I definitely was. I loved that Ana was no longer willing to settle for comfortable. This book also got me out of my reading slump 🥰
Displaying 1 - 9 of 9 reviews