Collateral

  THE GRAVITY OF SIN: BLOOD DEBT

  BOOK ONE

  KAYA V. DARKE

  EDEN EMBER

  Copyright © 2026 by Kaya V. Darke & Eden Ember

  All rights reserved.

  No part of this book may be reproduced in any form or by any electronic or mechanical means, including information storage and retrieval systems, without written permission from the author, except for the use of brief quotations in a book review.

  Formatted with Vellum

  For Spirit

  RIP Baby

  Contents

  Eden Ember

  Kaya V. Darke

  The Gavity of Sin: Blood Debt

  Collateral

  Leverage

  Trigger Warnings

  Talia

  1. Zane

  2. Talia

  3. Zane

  4. Talia

  5. Zane

  6. Talia

  7. Zane

  8. Talia

  9. Zane

  10. Talia

  11. Zane

  12. Talia

  13. Zane

  14. Talia

  15. Zane

  16. Talia

  17. Zane

  18. Talia

  Zane

  END

  Eden Ember

  Kaya V. Darke

  Eden Ember

  About the Author

  Eden Ember found her passion in writing sci-fi romance. She spends her days either pounding on the keyboard or dreaming up the next stories. Her active imagination never lets up and the perfect outlet comes through in her books.

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  Kaya V. Darke

  About the Author

  I wrote dark romance before dark romance even had a name, in the tumblr days when it was so taboo but it sucked everyone in anyway. I love being able to explore my passion for writing and sharing it with all of you.

  Make sure to follow me on Amazon to be notified of all my latest releases.

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  Visit KAYADARKE.COM for my contemporary dark romance works.

  The Gavity of Sin: Blood Debt

  Veridian-7, The Sapphire Cage, is an empire forged in psychic control and ruthless ambition.

  When its Empri patriarch vanishes, leaving a power vacuum and a galaxy on the brink, four women find themselves bound to the dangerous, blue-skinned brothers vying for control.

  They arrive as collateral, as leverage, as political pawns. But in the crucible of their captors' dark desires and galactic warfare, they will fight for agency, discover monstrous truths, and transform into something utterly new.

  The Gravity of Sin: Blood Debt is the first series in a saga of brutal choices, forbidden desires, and the terrifying, incandescent love forged when morally grey hearts collide under the shadow of a cosmic threat.

  Book One: Collateral

  Book Two: Leverage

  Book Three: Proxy

  Book Four: Void Bound

  Collateral

  My father's debt made me cargo. His mark made me his.

  TALIA

  I was dragged from my home in restraints, loaded into a cargo hold with twenty-two other souls, and shipped to the most dangerous station in the galaxy.

  Veridian Seven. The Sapphire Cage.

  I was supposed to disappear into the labor line, just another debtor ground down to nothing. But the syndicate lord who owns this station pulled me from the processing queue before I could draw my second breath of recycled air.

  Zane Torrence is seven feet of alien predator with bioluminescent skin, eyes like frozen methane, and an empathic ability that lets him feel every single thing I feel. My fear. My fury. My hatred.

  The things I feel when he's close that I refuse to name.

  He burned his mark into my throat. A brand of light that pulses with his heartbeat. Now everyone on this station knows what I am.

  His.

  But I am my father's daughter. I was raised to fix what's broken and survive what can't be fixed. And I will not break for a monster—no matter how badly the monster makes me want to.

  ZANE

  She was supposed to be leverage. A debtor with a dead father's secrets, nothing more.

  Then I felt her.

  Not her fear. Every human on this station reeks of fear. What stopped me cold was the defiance underneath. Structural. Load-bearing. The kind of defiance that forms the bones of a woman who has decided she will not break.

  I pulled her from the line before I made the conscious choice to move.

  I marked her before I understood why.

  Now she's in my quarters, learning my world, studying my weaknesses with those calculating grey eyes...and every night, through the bond I burned into her skin, I feel her wanting me and hating herself for it.

  My father built this empire on cruelty. He disappeared chasing something in the void and left me a station full of wolves. Enemies are circling. A traitor walks my corridors. And the woman I claimed as collateral is becoming the one thing I can't afford to lose.

  The difference between me and my father is the space between wanting and taking.

  Some days, that space is paper-thin.

  Collateral is a dark sci-fi romance featuring a possessive alien syndicate lord, a defiant captive mechanic, and an empathic bond neither of them asked for. This is Book One in the Blood Debt series and ends on a cliffhanger.

  Tropes: Captive/captor romance · Alien hero · Empathic bond · Touch her and die · Morally grey MMC · Strong FMC · Forced proximity · Dark sci-fi · Dual POV · He falls first · Spicy

  Leverage

  She came back for him. He'll burn the galaxy to keep her.

  ASTRA

  Six years ago, Dexter Torrence left me to die on a burning station.

  He calculated my survival odds—thirty percent—and chose the mission instead. I spent three weeks in enemy hands learning exactly what that choice cost. I spent six years after becoming someone who would never need rescue again.

  Then he walked back into my life.

  Seven feet of alien warrior with electric blue eyes and bioluminescent skin that glows with every emotion he can't hide. The man who abandoned me. The man I killed strangers for because they had his jawline, his walk, his ghost.

  The man I've never stopped loving, and I hate myself for it.

  Now we're hunting the traitor who sold us both—trapped on a stealth ship where the walls are too thin and his empathic abilities let him feel everything I'm trying not to feel. My rage. My grief. The want I've buried so deep it should be dead.

  It's not dead.

  And when the siege comes, when enemies close in and the station burns, I'll have to choose: my anger or my answers. The past or the future.

  Him or nothing.

  DEXTER

  I made the right call on Sigma-9. The math was clean. Thirty percent chance of saving her versus eighty percent mission success if I completed the extraction.

  I've run those ninety seconds a thousand times. The answer never changes.

  I left Astra Venn in a collapsing station and completed the objective, and she was taken, and tortured, and when she came back she was harder—sharper—a weapon that used to be a woman.

  I did that to her.

  Now she's the head of security on my brother's station, and she looks at me like I'm every sin she's ever committed wearing skin. She put a knife to my throat our first day back together. I let her draw blood because I've earned worse.

  But I can feel her through my abilities—the rage, the grief, and underneath it all, the thing she's trying to kill and can't: she still wants me.

  I'm not leaving this time. Not when enemies circle. Not when traitors walk our corridors. Not when the woman I destroyed six years ago is the only thing standing between my family and annihilation.

  Some equations don't have good answers.

  This one just has us.

  `

  Leverage is the second book in the Blood Debt series and features a military hero who left the heroine to die, second-chance romance forged in combat, and an empathic connection that makes hiding impossible. This book has a complete romantic arc but continues the overarching series plot.

  Tropes: Second chance romance · Military hero · Empathic abilities · Forced proximity on a ship · Touch her and die (this time he means it) · He grovels · She makes him work for it · Survival romance · Dark sci-fi · Dual POV · Hurt/comfort · Battle couple · Spicy

  Proxy

  She was made to be a weapon. He was built to steal her soul.

  AURA

  Fourteen years ago, my mother broke me in a cold room to see if I could hold a secret.

  I am the Zalt Consortium’s greatest achievement: a human dead-zone. I was trained to be a fortress of silence, a blade that feels no heat, a woman whose mind is a void the empathic Empri can never reach. I spent my life becoming a weapon that would never be turned.

  Then he walked into my life.

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  Ethan Eames. A half-alien chameleon with eyes like shifting storms and a silver tongue that has dismantled empires. The man the Torrences traded like currency. The man who reads every desire I’ve buried and mirrors them back until I don’t know where the lie ends and I begin.

  The man who is my husband by contract, and my ruin by choice.

  Now we’re trapped in the heart of a political web: bound by a marriage alliance where the rooms are too small and his presence is an anchor I never asked for. My walls. My silence. The hunger I’ve locked away so tight it should be dead.

  It's not dead.

  And when the anomalies open, when the stars turn wrong and the past comes screaming back, I’ll have to choose: my duty or my heart. The cage or the sky.

  Him or nothing.

  ETHAN

  I have lived a thousand lives, and every one of them was a lie.

  I am the perfect operative. I read the room, I find the crack, and I become the thing that opens it. I’ve spent a decade infiltrating the most dangerous family in the sector, but no one ever taught me how to read a woman who is a featureless blank.

  I can’t find her seams. I can’t feel her win.

  I was sold to Aura Zalt to settle a blood debt, and she looks at me like I’m a complication she’s calculating how to solve. She put a psychic suppressor on my neck just to see if I would bleed. I let her do it because I’ve never seen anything as beautiful as her reach.

  But I can see her through my training; the steel, the secrets, and underneath it all, the thing she’s trying to kill and can’t: she’s starting to want me.

  I’m not running this time. Not when the Consortium circles. Not when traitors move in the dark. Not when the woman who was built to be a weapon is the only thing keeping me from the void.

  Some secrets are meant to stay buried.

  This one is going to set us on fire.

  Proxy is the third book in the Gravity of Sin series and features a conditioned heroine who feels nothing, a chameleon hero who feels everything, and a marriage of convenience in a high-stakes galactic war. This book has a complete romantic arc but continues the overarching series plot.

  Tropes: Arranged marriage · Spy vs Spy · Emotional dead-zone heroine · Empathic protector hero · Forced proximity in shared quarters · He falls first · Touch her and die · Slow burn to high heat · Dark sci-fi · Dual POV · Hurt/comfort · Battle couple · Spicy

  Trigger Warnings

  Violence & Death

  Graphic violence — multiple scenes of hand-to-hand combat, killing, and physical brutality described in detail

  Murder / killing — protagonist kills multiple people; several on-page deaths by the MMC

  Assassination attempt — blade attack, close-quarters

  War / siege / armed conflict — full-scale station invasion with mass casualties

  Mass death / body count — civilian and combatant casualties during siege

  Gore — descriptions of blood, broken bones, crushed cartilage, neck-snapping, facial trauma

  Dead bodies — recovery of spaced bodies described in graphic detail; corpses on-page post-battle

  Weapons — firearms, blades, pulse weapons, shock batons used throughout

  Spacing (death by vacuum exposure) — threatened; past victims described in detail

  Execution / summary killing — on-page, by protagonist and MMC

  Captivity, Trafficking & Coercion

  Human trafficking — systematic debt-based trafficking presented as legal framework; humans transported in cargo holds

  Kidnapping / abduction — FMC forcibly taken from her home by armed operatives

  Forced captivity / imprisonment — FMC held against her will for the duration of the book

  Restraints / being bound — handcuffs, zip ties, physical restraint in multiple scenes

  Slavery / indentured servitude — debt bondage system central to the worldbuilding; people processed as labor assets

  Branding / forced marking — FMC is branded with a bioluminescent mark on her throat without meaningful consent

  Dehumanization — people referred to as "cargo," "inventory," "assets"; processed through intake systems

  Forced compliance — threats of violence ("spacing") for resistance; forced kneeling as protocol for debtors

  Power imbalance / dubious consent dynamics — the sexual relationship exists within a captor/captive framework with significant power disparity (see note below)

  Sexual Content & Consent Complexity

  Explicit sexual content — multiple detailed sex scenes

  Breath play / choking during sex — consensual but within a coercive broader context

  Rough sex — biting, bruising, scratching, wall sex, hair-pulling, physical intensity

  Oral sex (performed on FMC) — explicit

  Dubious consent framing — while the FMC verbally consents and initiates in most scenes, the broader context of captivity, ownership, and power imbalance means meaningful free consent is structurally compromised; the text engages with this tension directly but does not resolve it

  Possessive / controlling sexual dynamics — MMC exhibits extreme possessiveness framed as protection

  Surveillance of intimate moments — MMC watches FMC through security cameras, including while she sleeps

  Emotional & Psychological

  Emotional manipulation — empathic abilities used to read and influence emotions without consent; half-Empri character potentially manipulates a young woman through touch

  Psychological coercion — FMC coerced into becoming an informant in exchange for medical care for others

  Gaslighting-adjacent dynamics — MMC frames captivity and branding as "protection"

  Betrayal — FMC informs on people who trusted her; deep-cover spy revealed within inner circle

  Grief / parental loss — both protagonists dealing with missing/presumed dead fathers; grief is a central emotional thread

  Abandonment — FMC's father knowingly left her as collateral; MMC's father voluntarily disappeared

  Isolation / loss of community — FMC is progressively cut off from debtor community as she aligns with her captor

  Identity loss / identity crisis — FMC grapples extensively with who she is becoming

  Moral compromise — FMC's arc involves informing, killing, and aligning with a criminal syndicate; internal conflict over complicity

  Guilt and shame — depicted in detail, particularly around sexual desire within captivity and informing on vulnerable people

  Physical Harm & Medical

  Forced medical examination — FMC stripped and examined without meaningful consent; body scanned, blood drawn

  Forced stripping — FMC ordered to undress in front of armed guards

  Bruising / physical injury — frequent; bruises from restraints, combat, and sex described in detail

  Starvation / food deprivation — FMC goes days without food; debtors kept on minimal rations

  Sleep deprivation — referenced for FMC and multiple characters

  Untreated illness — debtor denied medical care; pneumonia left untreated due to systemic neglect

  Inadequate medical care based on social status — tiered healthcare system where debtors receive minimal treatment

  Systemic & Structural

  Debt bondage / predatory debt systems — inherited debt, fraudulent contracts, people seized as collateral

  Class-based oppression / classism — rigid hierarchy between syndicate elites and indentured debtors