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Twisted Sin
In a world where hope was dim,
Two siblings, Fin and Barbie, were torn from kin.
An older brother, strong and kind,
A little sister, innocent and intertwined.
Her smile, her laugh. Fin remembered it all,
Until they snatched her out of his arms.
Separated by a fate unkind and unfair,
Thrown into foster care, their hearts laid bare.
Forced into Murdoch’s cold embrace,
A place where shadows lingered in every space.
They called him insane, though he held on to a dream,
To find his sister, to mend the broken seam.
Seven long years, a lifetime it seemed,
Barbie, too, was lost in a twisted dream.
Into the same asylum, their paths would align,
A reunion in the darkness, a moment divine.
In the midst of madness, their love would persist,
For Fin and Barbie, each other they’d assist.
No more separation, no more endless despair,
Together they’d weather any storm they’d bear.
Fin vowed never to let his Barbie go,
To slit the throats of any man who tip-toed too close.
Their twisted sin,
Now cemented with no end.
Two siblings, Fin and Barbie, were torn from kin.
An older brother, strong and kind,
A little sister, innocent and intertwined.
Her smile, her laugh. Fin remembered it all,
Until they snatched her out of his arms.
Separated by a fate unkind and unfair,
Thrown into foster care, their hearts laid bare.
Forced into Murdoch’s cold embrace,
A place where shadows lingered in every space.
They called him insane, though he held on to a dream,
To find his sister, to mend the broken seam.
Seven long years, a lifetime it seemed,
Barbie, too, was lost in a twisted dream.
Into the same asylum, their paths would align,
A reunion in the darkness, a moment divine.
In the midst of madness, their love would persist,
For Fin and Barbie, each other they’d assist.
No more separation, no more endless despair,
Together they’d weather any storm they’d bear.
Fin vowed never to let his Barbie go,
To slit the throats of any man who tip-toed too close.
Their twisted sin,
Now cemented with no end.
110 pages, ebook
First published January 12, 2024
7 people are currently reading
256 people want to read
About the author
Natalie Knight
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Displaying 1 - 21 of 21 reviews
March 2, 2024
Why mark the book as a ‘Virgin heroine’ and then have the poor female character go through the trauma of SA after meeting the Hero.
⛔️SPOILER- ⛔️
.
.
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There’s a 1 year time separation and the heroine is forced to marry another man and forced to give him sex
⛔️SPOILER- ⛔️
.
.
.
There’s a 1 year time separation and the heroine is forced to marry another man and forced to give him sex
Read
January 20, 2024I like the forbidden angle to be played up more in taboo books and it wasn’t here at all. It’s a lot of just shock value stuff.
January 18, 2024
Twisted Sin is a Dark Taboo novella that Is a quick and spicy read I needed to get out of my book funk. I have always loved dark and taboo.
Check your triggers, and this book is not for everyone.
When Barbie and Fin unexpectedly come face-to-face at the Murdoch Home for the mentally disturbed, after years of being apart, their reunion is an intense and explosive affair that will leave you on the edge of your seat!
There is a small plot, but I wasn't too concerned as I was primarily interested in reading a spicy book. The plot was enough to keep my attention.
Check your triggers, and this book is not for everyone.
When Barbie and Fin unexpectedly come face-to-face at the Murdoch Home for the mentally disturbed, after years of being apart, their reunion is an intense and explosive affair that will leave you on the edge of your seat!
There is a small plot, but I wasn't too concerned as I was primarily interested in reading a spicy book. The plot was enough to keep my attention.
January 25, 2024
Taboo where? Disappointed
June 11, 2025
“My little asylum darlin.” He stopped laughing and titled his head
sideways, looking at me as though he saw me for the first time. “If I were to
ever fall in love, I think I would fall in love with you.”
Oh Fin. You sir are crazy but I'm here for it. This book is dark and twisted and perfect. I honestly loved it so much! The author did an amazing job with this one.
sideways, looking at me as though he saw me for the first time. “If I were to
ever fall in love, I think I would fall in love with you.”
Oh Fin. You sir are crazy but I'm here for it. This book is dark and twisted and perfect. I honestly loved it so much! The author did an amazing job with this one.
January 20, 2024
Wtf did I just read?! 🥴🥴
▬ 𝐭𝐫𝐨𝐩𝐞𝐬: dark romance, taboo, asylum/hospital
▬ 𝐭𝐰: abuse, sexual abuse, violence, death, incest (brother x sister)
▬ 𝐭𝐫𝐨𝐩𝐞𝐬: dark romance, taboo, asylum/hospital
▬ 𝐭𝐰: abuse, sexual abuse, violence, death, incest (brother x sister)
March 17, 2024
I love anything set in an asylum. This kinda reminded me of That Sick Luv or Sick Fux. It just had that vibe. Quick, easy read.
February 23, 2024
CREEPED ME TF OUT, BUT STILL HOT
s h e l v e s :
alpha
dark
possessive
protective
virgin h
k i n k s :
bdsm
breath play
breeding
degradation
dirty talk
dom
exhibition
no condom
rough sex
praise
taboo (brother x sister)
tss
💦
endearments
♥︎ princess
r e v i e w :
SPOILER WARNING.
Fin and Barbie are brother and sister that were separated when put into foster care. They’re both kind of…psycho. Fitting since they meet up again in a psych ward facility. Fin has major homicidal anger issues. He gets a thrill from killing and hurting people. That creeped me out. Barbie is just obsessed with sex and her foster parents are super cult vibes religious, so they sent her here to be “fixed.”
Fin & Barbie are immediately attracted to each other and fuck at every opportunity. The sex was hot, but their situation stressed me out. I felt trapped, which I guess is a testament the writing, but 😭. I just hated that feeling, like I was stuck in a nightmare. Not really what I’m looking for when I pick up a book. The doctor at the facility is a sexual predator and forces Fin to fuck her, and fabricates stuff on his file so that he can never leave.
They do get their happy ending outside of the psych place. It was creepy when Fin went out on a killing spree and brought Barbie back the hearts tho.
h o t c l i p s :
I pounded into my therapist as she screamed at the top of her lungs, her hips hitting against the desk. I thrust harder against her, making sure it bruised her skin enough to leave a mark. I wanted her to hurt. I wanted this bitch to suffer for humiliating me like this. A tall man dressed in purple scrubs stood behind me, holding my wrists, bound tightly with thick, red rope.. Another man dressed in similar attire held a whip, bringing it to my back whenever the bitch below me commanded it. Her idea of mingling was my cock slamming into her cunt.
“Harder… harder.” She moaned. I pulled out all the way and slammed back into her with enough force to move the table. I watched as her back arched from the impact.
She lay still, trying to catch her breath. “Get off.”
She picked up a box of tissues and threw it at me. “Clean yourself off. Our meeting is about to end.” She chuckled to herself before getting fully dressed. The guards untied me.
I plucked a few tissues and wiped the cum off my cock before shoving it back into my pants.
…
“I’d love it more if you choked on my cock and dropped dead, slut,” I spat, but that only made her smile grow more.
♥︎
The pain in my pants grew even tighter, and I had to shift to relieve some of the pressure.
My Barbie had come to pay a visit.
♥︎
“If anyone is going to slide their cock between your legs, it’s going to be me. If anyone gets to rape you, it will be ME.”
Heat spread through me as I imagined him fucking me. I squeezed my legs tightly, wanting to relieve some of the pressure that built up from his cruel words.
♥︎
A gasp left her lips as my fingers slipped between her pussy lips.
♥︎
I spun her around and slammed her against the wall, using my foot to spread her legs open.
“Scream for me,” I said and forced my cock into her virgin hole.
I fucked her relentlessly. Then I did it again. I pressed her face harder against the cool wall, the sound of my cock sliding in and out of her cunt coating the air.
♥︎
I wanted to be taken like that. When I was younger, I used to sneak and watch rough sex porn videos. The ones where the men would pound into the women from behind. I wondered what that felt like.
A spark went off in me as images of him over me came flooding back. Sweat covered his brow and glistened on his chest.
♥︎
I saw the dark lines of mascara running down her cheeks, the telltale sign of tears shed in pain. The thought of causing those tears with every hard thrust of my cock only made me want her more.
I held the side of her head and pounded ferociously into her mouth.
Tears pooled at the corners of her eyes once more, but I ignored them. Ignored everything but the building pleasure before releasing myself into her.
♥︎
I pulled her towards me, her hands coming to my chest. I dipped a finger into the top of her shirt and pulled it back to reveal a kiss mark just above her breast. I smiled in delight that the mark hadn’t faded, then released her.
♥︎
“Tell me who that tight little cunt belongs to.” I slid my tongue out, and let drool coat my tatted fingers.
She opened for me and pulled her panties to the side. “My savior’s cunt.”
♥︎
I watched as she downed the water, never coming up for air. Without thinking, I brought my lips to her throat and bit down gently.
She gasped. “What was that?”
I just shrugged. “How else was I supposed to say I suddenly felt like marking you?”
I ignored her gasps of protest and smiled, wrapping my arms around her torso and resting my head on her lap. She causally brought her hand to my head and stroked my hair. I closed my eyes, reeling in the feel of her.
♥︎
He spread my legs and lowered to his knees.
“The prettiest cunt I’ve ever seen.” He slid a finger down my pussy, and licked it. “I love the way my sister tastes.”
He stood and pulled off his pants, revealing his thick, throbbing cock. The sight of it made my heart race and my pussy ache to be filled.
♥︎
My hips met his thrusts with urgency and wild abandon as we moved in perfect unison.
“My Barbie.”
s h e l v e s :
alpha
dark
possessive
protective
virgin h
k i n k s :
bdsm
breath play
breeding
degradation
dirty talk
dom
exhibition
no condom
rough sex
praise
taboo (brother x sister)
tss
💦
endearments
♥︎ princess
r e v i e w :
SPOILER WARNING.
Fin and Barbie are brother and sister that were separated when put into foster care. They’re both kind of…psycho. Fitting since they meet up again in a psych ward facility. Fin has major homicidal anger issues. He gets a thrill from killing and hurting people. That creeped me out. Barbie is just obsessed with sex and her foster parents are super cult vibes religious, so they sent her here to be “fixed.”
Fin & Barbie are immediately attracted to each other and fuck at every opportunity. The sex was hot, but their situation stressed me out. I felt trapped, which I guess is a testament the writing, but 😭. I just hated that feeling, like I was stuck in a nightmare. Not really what I’m looking for when I pick up a book. The doctor at the facility is a sexual predator and forces Fin to fuck her, and fabricates stuff on his file so that he can never leave.
They do get their happy ending outside of the psych place. It was creepy when Fin went out on a killing spree and brought Barbie back the hearts tho.
h o t c l i p s :
I pounded into my therapist as she screamed at the top of her lungs, her hips hitting against the desk. I thrust harder against her, making sure it bruised her skin enough to leave a mark. I wanted her to hurt. I wanted this bitch to suffer for humiliating me like this. A tall man dressed in purple scrubs stood behind me, holding my wrists, bound tightly with thick, red rope.. Another man dressed in similar attire held a whip, bringing it to my back whenever the bitch below me commanded it. Her idea of mingling was my cock slamming into her cunt.
“Harder… harder.” She moaned. I pulled out all the way and slammed back into her with enough force to move the table. I watched as her back arched from the impact.
She lay still, trying to catch her breath. “Get off.”
She picked up a box of tissues and threw it at me. “Clean yourself off. Our meeting is about to end.” She chuckled to herself before getting fully dressed. The guards untied me.
I plucked a few tissues and wiped the cum off my cock before shoving it back into my pants.
…
“I’d love it more if you choked on my cock and dropped dead, slut,” I spat, but that only made her smile grow more.
♥︎
The pain in my pants grew even tighter, and I had to shift to relieve some of the pressure.
My Barbie had come to pay a visit.
♥︎
“If anyone is going to slide their cock between your legs, it’s going to be me. If anyone gets to rape you, it will be ME.”
Heat spread through me as I imagined him fucking me. I squeezed my legs tightly, wanting to relieve some of the pressure that built up from his cruel words.
♥︎
A gasp left her lips as my fingers slipped between her pussy lips.
♥︎
I spun her around and slammed her against the wall, using my foot to spread her legs open.
“Scream for me,” I said and forced my cock into her virgin hole.
I fucked her relentlessly. Then I did it again. I pressed her face harder against the cool wall, the sound of my cock sliding in and out of her cunt coating the air.
♥︎
I wanted to be taken like that. When I was younger, I used to sneak and watch rough sex porn videos. The ones where the men would pound into the women from behind. I wondered what that felt like.
A spark went off in me as images of him over me came flooding back. Sweat covered his brow and glistened on his chest.
♥︎
I saw the dark lines of mascara running down her cheeks, the telltale sign of tears shed in pain. The thought of causing those tears with every hard thrust of my cock only made me want her more.
I held the side of her head and pounded ferociously into her mouth.
Tears pooled at the corners of her eyes once more, but I ignored them. Ignored everything but the building pleasure before releasing myself into her.
♥︎
I pulled her towards me, her hands coming to my chest. I dipped a finger into the top of her shirt and pulled it back to reveal a kiss mark just above her breast. I smiled in delight that the mark hadn’t faded, then released her.
♥︎
“Tell me who that tight little cunt belongs to.” I slid my tongue out, and let drool coat my tatted fingers.
She opened for me and pulled her panties to the side. “My savior’s cunt.”
♥︎
I watched as she downed the water, never coming up for air. Without thinking, I brought my lips to her throat and bit down gently.
She gasped. “What was that?”
I just shrugged. “How else was I supposed to say I suddenly felt like marking you?”
I ignored her gasps of protest and smiled, wrapping my arms around her torso and resting my head on her lap. She causally brought her hand to my head and stroked my hair. I closed my eyes, reeling in the feel of her.
♥︎
He spread my legs and lowered to his knees.
“The prettiest cunt I’ve ever seen.” He slid a finger down my pussy, and licked it. “I love the way my sister tastes.”
He stood and pulled off his pants, revealing his thick, throbbing cock. The sight of it made my heart race and my pussy ache to be filled.
♥︎
My hips met his thrusts with urgency and wild abandon as we moved in perfect unison.
“My Barbie.”
May 30, 2024
2.5 stars
- FMC: Barbie
- MMC: Fin
- POVs Included: Dual POVs (Fin, Barbie)
-----------------------------------
-----------------------------------
SUMMARY: (SPOILER WARNING)
Fin and his younger sister Barbie were separated in the foster system many years ago. Now they have both ended up locked in the same insane asylum -- Murdoch Home for the Mentally Disturbed.
Barbie isn't sure Fin recognizes her at first, but she recognizes him. And he does recognize her too. But now that they've reunited, their feelings for each other have warped and no longer normal.
Now all they want to do is get out and spend their lives together.
-----------------------------------
-----------------------------------
REVIEW:
Meh. This was just okay.
The premise is interesting, but it's all very rushed and just not very well fleshed out.
There's also some very big plot holes going on....
First, if she's technically 18 (even if it's a new 18), then her adoptive parents cannot have her committed to a mental asylum for masturbating. That's absurd. I know I'm supposed to suspend belief for some books, but c'mon.
Another thing, there is absolutely no way that the asylum would've offered a violent, murderous and dangerous patient like Fin an opportunity to leave if he stayed on his best behavior after having just attempted to murder his perverted therapist. Mind you, he also already DID murder Barbie's therapist. So yeah, this isn't even a remote possibility.
Again, I know sometimes we need to suspend belief while reading smut. But I think the author could've done better here.
I also didn't find the steam very good. It was just meh.
Overall it was just a little boring and not very well written. I liked the premise, but not the execution.
- FMC: Barbie
- MMC: Fin
- POVs Included: Dual POVs (Fin, Barbie)
-----------------------------------
-----------------------------------
SUMMARY: (SPOILER WARNING)
Fin and his younger sister Barbie were separated in the foster system many years ago. Now they have both ended up locked in the same insane asylum -- Murdoch Home for the Mentally Disturbed.
Barbie isn't sure Fin recognizes her at first, but she recognizes him. And he does recognize her too. But now that they've reunited, their feelings for each other have warped and no longer normal.
Now all they want to do is get out and spend their lives together.
-----------------------------------
-----------------------------------
REVIEW:
Meh. This was just okay.
The premise is interesting, but it's all very rushed and just not very well fleshed out.
There's also some very big plot holes going on....
First, if she's technically 18 (even if it's a new 18), then her adoptive parents cannot have her committed to a mental asylum for masturbating. That's absurd. I know I'm supposed to suspend belief for some books, but c'mon.
Another thing, there is absolutely no way that the asylum would've offered a violent, murderous and dangerous patient like Fin an opportunity to leave if he stayed on his best behavior after having just attempted to murder his perverted therapist. Mind you, he also already DID murder Barbie's therapist. So yeah, this isn't even a remote possibility.
Again, I know sometimes we need to suspend belief while reading smut. But I think the author could've done better here.
I also didn't find the steam very good. It was just meh.
Overall it was just a little boring and not very well written. I liked the premise, but not the execution.
This entire review has been hidden because of spoilers.
January 17, 2024
Fin and Barbie are bl••d siblings who were separated when they were much younger and placed into an “asylum” based foster system. Fin himself received psychiatric care that was based on unorthodox methods such as schm3xual punishments, shaping him into the type of person that one would describe as insane. The only thing that got him through the years were thoughts of his younger sister. His only goal was to reunite with her. However, Barbie’s new family has other plans for her.
“Twisted Sin” is so different from the other books I’ve read by Natalie Knight. It’s very dark and intense. I enjoyed the pacing and still captured the Natalie Knight taboo factor throughout the story.
TW/CWs: Bl••d Iñç•st( brother and sister), D3gr•d•tion, Touch her and you d¡3, Asylum vibes, V¡rgin FMC, Br33ding, Presenting the hearts of her enemies, Little to no plot.
“Twisted Sin” is so different from the other books I’ve read by Natalie Knight. It’s very dark and intense. I enjoyed the pacing and still captured the Natalie Knight taboo factor throughout the story.
TW/CWs: Bl••d Iñç•st( brother and sister), D3gr•d•tion, Touch her and you d¡3, Asylum vibes, V¡rgin FMC, Br33ding, Presenting the hearts of her enemies, Little to no plot.
January 24, 2024
I liked the idea of this but I honestly didn’t feel it being forbidden much. I would have liked the realization from the H that it was his sister that he was attracted to. We get his pov from seeing the h again after years and it seemed like he didn’t recognize her… then in the h’s pov after he mentions wanting to f**k her we realize he already knows it’s his sister… 🤔 I definitely didn’t feel the forbidden aspect of them at least fighting it a tinny tiny bit. We also never get his pov of him thinking about his sister or anything related to his sister in the beginning before he says her again, I just thought that was kinda weird? No?
Anyways I did like it but I would loved the forbidden aspect of the relationship played up a lot.
Anyways I did like it but I would loved the forbidden aspect of the relationship played up a lot.
January 28, 2024
OOF. Juicy taboo!!! Fin / Barbie
They see each other for the first time in years at an asylum.
Fin is being sexually abused by the director of the asylum, and Barbie is forced by her foster parents because she likes to tickle her pickle too much .
Tons of TW incest, rape, knife play, abuse, murder, drugs, religious abuse
Anyways, they hang out for a month, she gets sent home & is forced by her foster parents to be with an older man...
The ending was satisfying.
"Your body is a temple I want to defile, and your soul... I want to shatter it into a thousand pieces."
Ps- you can download this on her website. It is not on Kindle.
They see each other for the first time in years at an asylum.
Fin is being sexually abused by the director of the asylum, and Barbie is forced by her foster parents because she likes to tickle her pickle too much .
Tons of TW incest, rape, knife play, abuse, murder, drugs, religious abuse
Anyways, they hang out for a month, she gets sent home & is forced by her foster parents to be with an older man...
The ending was satisfying.
"Your body is a temple I want to defile, and your soul... I want to shatter it into a thousand pieces."
Ps- you can download this on her website. It is not on Kindle.
January 17, 2024
Did someone say dark and taboo romance? Yes. We all know I would be invested. Fin and Barbie were exactly wanted I needed. These two are reunited after years of being separated and their coming together is fire. Is this your typical dark taboo romance? Nope because this blood brother and sister. Was it crazy? Yes. Was I invested? Yes. Even though this is a heavily taboo book I can still read it and separate myself from it.
May 5, 2024
Meh
Loved how crazy Fin was and how innocent Barbara was but the execution just felt... meh. The build-up of them getting together fizzled as did Fin getting revenge on Grant and Knight completely bypassed Fin going after Harkness.
There were so many plot holes such as what happened to Barbara's parents? Grant is gone but was in the underground so how did Fin handle that since he's in the life too?
Loved how crazy Fin was and how innocent Barbara was but the execution just felt... meh. The build-up of them getting together fizzled as did Fin getting revenge on Grant and Knight completely bypassed Fin going after Harkness.
There were so many plot holes such as what happened to Barbara's parents? Grant is gone but was in the underground so how did Fin handle that since he's in the life too?
September 13, 2025
Twisted Sin by Natalie Knight is a short dark taboo novella and this one was soooo good! When Barbie and Fin estranged brother and sister end up in an asylum they become reconnected and soon find they can’t get enough of each other. Please check those triggers, I know everyone is not comfortable with incest but worth a read if you’re ok with it.
January 21, 2024
Fin + Barbie
-brother/sister taboo
-asylum
-protector
-dark romance
if they don’t present me the hearts of my enemies…i don’t want it.
-brother/sister taboo
-asylum
-protector
-dark romance
if they don’t present me the hearts of my enemies…i don’t want it.
March 20, 2024
Dark, twisted, bloody, and taboo!!!! I loved it!! Fin and Barbie were HOT!!!
May 3, 2025
Okay, I'm sick in the head like many others who have read it. Overall, it was good but short.
August 9, 2025
uh. no.
I have no triggers, nothing shocks me anymore and I inhale the nasty taboo stuff. so I should have liked this? nah.
It was like some weird crack-head dream-cest-topia.
I have no triggers, nothing shocks me anymore and I inhale the nasty taboo stuff. so I should have liked this? nah.
It was like some weird crack-head dream-cest-topia.
Displaying 1 - 21 of 21 reviews