Nyx (Mate's Mark Book 3), page 1
Nyx
G. Eilsel
Copyright © 2025 G. Eilsel
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.
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Contents
Dedication
Introduction
Content Warnings
Pronunciation Guide
Map
Military Rank
1. Nyx
2. Reyes
3. Reyes
4. Nyx
5. Reyes
6. Nyx
7. Reyes
8. Nyx
9. Reyes
10. Nyx
11. Reyes
12. Nyx
13. Reyes
14. Reyes
15. Reyes
16. Nyx
17. Reyes
18. Nyx
19. Reyes
20. Reyes
21. Nyx
22. Nyx
23. Reyes
24. Nyx
25. Nyx
26. Reyes
27. Nyx
28. Reyes
29. Nyx
30. Reyes
31. Nyx
32. Reyes
33. Nyx
34. Reyes
35. Nyx
36. Reyes
37. Nyx
38. Reyes
39. Reyes
40. Nyx
41. Reyes
42. Reyes
Chapter
Updated Map
Monster Guide
Monster Guide
Monster Guide
Monster Guide
Monster Guide
Monster Guide
Monster Guide
Military Ranks by Character
Author's Note
Special Thanks
Other Books by G. Eilsel
Dedication
This one is dedicated to those who suffer in silence. The ones who scream into pillows and bite their tongues, and muffle their cries with their palms to hold it all inside. Those who’ve lived with the pain so long that some days it feels like a friend.
Let it out.
Scream it to the heavens if that's what it takes.
Your voice deserves to be heard.
If you're following the count, the word "cock" is used 57 times, this time over 430 pages.
You're welcome.
Introduction
It is highly recommended to read these books in order, as the storyline is continuous in the series and I do not consider these to be standalone. The series begins with Book 1: Ronan.
Nyx is an MM fated mates monster romance that takes place in a dystopian future where monsters have invaded and taken control of humanity. The merging of the worlds affected the climate as well, and Earth is no longer lush and beautiful, but barren and dry. Most of the human population live under the control of the monsters, locked behind the walls surrounding the cities that remain standing. Rebel groups and ramblers live in the wilds, where safety is never guaranteed, and every day is a fight for survival.
It was long believed that the passageways between the realms have been closed and the monsters’ world has been destroyed, but in Elas, we learn that things are not as they seem. At the end of book 2, August and Elas have infiltrated Ljómur and subsequently destroyed the base, killing those in charge. They have returned to the village along with the medic Xeni, Taryn, and Lillith. Xeni confirms the military has been trying to open the rifts. They have been using Nyx, who now knows where many of these passages are located.
This book's timeline follows that of book 2, and begins approximately a month after Elas ends.
These stories have a guaranteed HEA, though individual books end on what I’d consider a HFN (Happy For Now) between the MCs. There is a major overarching storyline, and this series is best read in order. Inevitably, some questions are left unanswered, and although this book has a resolution to the immediate issues and problems dealt with by the MCs, it ends on what I’d consider a cliffhanger as it leads into the next.
Content Warnings
Listed below is a breakdown of content that some readers may find hard to read. Please note that these warnings may contain spoilers, and while this may not be a complete list, I’ve done my best to include any potentially triggering material.
Explicit sexual content between a human and non-human coupling
Use of weapons - including swords, knives, and guns
Extreme violence, including many on-page deaths and permanent maiming
Blood and gore
Kidnapping and imprisonment, including discussions of extreme confinement
Severe depression, anxiety, and PTSD of an MC – current, detailed on page struggles
Suicidal Ideation and Attempts by an MC – in the past, detailed on-page discussion. Includes self-inflicted starvation, cutting, and inciting anger of others as a means to end life.
Violence towards a dog – in the past, flashback of near-lethal injuries. I chose not to go into heavy detail on this, though the injury itself is on page.
Military setting, which includes receiving and obeying unlawful orders
Discussion of an MC being sold into child sexual slavery – in the past, with no actual SA happening.
Mention of a Mate dying – side character, not in detail
Discussions of suspected infertility as a result of medical experimentation
Detailed, on page torture that includes: confinement to a cage, starvation, water deprivation, use of shock collars, physical violence, restraints, captivity, leading up to death and resuscitation.
Detailed discussion of medical experimentation that includes: injecting experimental medicines, draining of blood/exsanguination, psychological and physical torture for the sake of being studied
Pronunciation Guide
Names
Ronan: ROH-nan
Elas: EHL-us
Nyx: NIX
Xeni: ZEN-ee
Matuk: muh-TUK
Aeliphis: uh-LIHF-is
Bravis: BRAH-vis
Khors: KORS
Aryn: AIR-en
Daiwynn: DAY-win
Species
Anunian: uh-NEW-nee-an
Nu'vak: NEW-vak
Drüinae: DREW-in-ay
Cavese: cuh-VEES
Khileon: KILL-ee-on
Ramves: RAMS
Bhotan: BOH-tuhn
Curtiphan: KURT-ih-fan
Lu'Mite: LOO-mite
Lindae: LIN-day
Others/Miscellaneous
Mo'sziv: mo-SEEV
Ljómur: LO-muhr
Glaston: GLASS-ton
Katsurrel: kat-SIR-el
Sirrha: SEER-uh
Nyx
The world is silent, and I am weightless.
Soft ripples of sunlight dance and shimmer from above, the rays reaching through the water to caress my face. Tiny bubbles cascade around me and float towards the sky, bobbing lazily upward as an exhale pushes from my lips. Their shadows disrupt the stream of sunshine, but most of them never break the surface.
Most of them never escape.
The burgeoning happiness in my chest stalls in my throat, lodging itself in my windpipe until I choke on its memory. It would steal my breath if I wasn’t already holding it, but the lack of oxygen doesn’t bother me. Rough hands and metal collars have stolen my ability to breathe for so long, my body is numb to the instinct that begs me to give it precious fuel.
You are free, I remind myself.
You escaped.
Free.
Free.
My lungs ache with the need to take in fresh air, but I’m not ready to give up the tranquility of this place. Down here, everything is quiet.
The voices.
The memories.
The world.
Thick clusters of bubbles cling to my skin, and the sun beats harder, coaxing me to leave this watery grave. But leaving means thinking. It means breathing, hearing, and seeing. Feeling.
I just want a moment where I don’t feel anything at all.
I feel too much in this place. Sorrow and confusion, mostly, but there’s relief hiding between them. A deep yearning for connection that I don’t know how to fulfill, and phantom memories of happier times that I can’t bring to light.
I don’t know what to do with any of it.
Ljómur was hell on Earth, but at least I could be empty. Could live in this hollow chest and thrive inside the desolation of a mind wiped clean. Let gravity hold this husk of a body to the ground while life passed around me.
It’s wrong to miss it, but I do.
No one cared when I detached… when I retreated into this void, and my existence was erased from this world. I was forgotten so thoroughly that I questioned whether I had ever truly been there.
Maybe I disappeared altogether.
Maybe I could
It would be easier.
There, it went unnoticed when I got lost in the recesses of my mind. I could escape to this snowy white, staticky void without the questions. Without the incessant attempts to cheer me up, or the efforts to make me engage, or the never-ending, soothing whispers that ask if I’m alright.
I’m not alright. Of course I’m not. The world has moved on, has changed, and I no longer fit in this life.
Sometimes I can pretend.
Sometimes it almost feels real.
But I don’t know how to belong.
The only world I understand is cold floors and threadbare blankets. Barred doors and hunger and pain. Apologies for everything I’m doing wrong that never seem to reach the ears of the hands that bind me. Silent tears and I’m sorry and wishing for the darkness to carry me away from it all.
A warbled sound leaves my mouth, taking with it the last of my oxygen. My cries are lost to the water’s embrace, and my tears are mere drops within this larger, ever-moving pool. They’re unsubstantial, as has always been my fate.
The edges of the world soften as ringing fills my ears, but still, I hold on. I float.
Exist.
It’s all I’ve ever known how to do.
Muffled sounds find me through the water, and a deep voice calls out in the distance. My time in this sanctuary is over, whether I’m ready to face the world or not. Pain stabs through my chest, and my lungs lurch behind my ribcage as my body pleads for air. I take one last glance around my silent tomb before I heed its demand.
Reflections dance across the storm of my hair. A tadpole zips between the floating strands, wiggling its tail as if it’s matching their movement. The voice yells again, closer now, and the tiny creature darts away to hide from the intrusion.
My time hiding is done, though.
I release my grip on the log that anchors me here. A single kick of my feet propels me upward, and I drift towards that ring of light. The once glass-smooth surface turns turbulent as I float higher, and as I break through, the world finds me in a rush of lights and sounds.
The sun that was a faint lamp underneath the water now beats on my skin, blazing hot and blinding. Leaves rustle from the wind, but it might as well be claws against my eardrums. I glance over my shoulder as feet crunch against the fallen twigs and underbrush, still treading water in the lily pad ring of my hair.
“There you are,” Ronan says as he emerges from the trees. “I was looking everywhere for you. Did you forget about our lesson?” I shake my head, scrunching my nose at the droplets that tickle my face. Sympathy burns off his expression as he crosses his arms and nods. “Do you not feel like it today?”
“No, I just—”
“In English, Nyx,” he scolds in the firm tone he uses when he teaches me. I glare at him, but he only snorts a laugh and crouches near the water’s edge, his voice infinitely softer. “You’re the one who told me to make sure you stick with it, even when you don’t want to.”
“I said, yes. Did not mean. That was when I was not…” I glance around us, trying to remember the word. “Busy.”
His lips twitch. “Busy doing what? Pretending to be a frog?”
Water sloshes as I lift a hand out to point at him. “You are the whole ass.”
“You mean an asshole?” he corrects with a smirk.
“No. The whole thing. Ass. Whole ass, Ronan.”
He tosses his head back in a loud laugh, and I begrudgingly let the sound lift my spirits by a fraction. “Who knew there was an entire giant ball of sass in there?” Ronan says with a chuckle, and I swim towards the shore.
“No sass,” I say as I wring out my hair. “Just frog.”
He grins again, but his smile fades as he watches me. “Do you need to skip our lesson today? Would you be happier if you stayed in the water?”
Yes.
Yes, it would make me happier to float in the depths and hide. Lock myself away in this isolation and sentence myself to a life of solitude. Anchor myself to that log and refuse to move.
Disappear.
But the world continues to spin as I stand still. I have to make an effort to catch up, even if it’s tiptoed steps and stumbling strides. Water sluices down my chest as my feet find the sandy, pebbled soil near the shore. “No, I come. My skin is…” I scrunch my nose again and display the pads of my fingers to him.
“Wrinkly.”
“Reen-clee?” I try, then scoff and shake my head. “No sense.”
Ronan makes an exasperated noise as I step out of the water, and I tilt my head at him in question. “We’ve talked about modesty, Nyx,” he scolds as he pointedly looks away, and thick, uncomfortable shame compresses my chest. “You shouldn’t walk around without clothes unless you’re at home.”
Home.
The forest is my home, or the closest I have to one, though I don’t argue that point.
Crystal droplets from the creek roll down my skin as my eyes drop to my naked body. Fat and muscle are slow to build, and prominent ribs line my torso—shadowed peaks and valleys that are too stubborn to fill. My knees and elbows are thicker than my arms and legs, and my hands and feet look too big.
Still, subtle changes are coming to my body as weight finds its way onto my frame, even if it isn’t as fast as Ronan prefers. He complains when I don’t eat his meat. He says I need it, but I don’t. It doesn’t feel right to consume the only creatures in this place who have never hurt me, though I’d never judge the others for feeding themselves.
Starvation is a special sort of pain.
I tear my eyes from my nakedness to Ronan’s back facing me, his arms crossed as he waits. Worrying about something as trivial as skin seems so silly. Modesty wasn’t an option in Ljómur. When you wore holes in your clothes, or they were too filthy to wear anymore, you did without until someone thought to bring you more. Bathing and relieving yourself, eating and sleeping were done under the watchful eyes of others.
I existed only to be observed. Even when the medics didn’t pull me for more tests, or the scientists didn’t need me for another experiment, my life was spent in an eight-by-six cell. No solid door to hide behind. No privacy.
A toy in a glass display.
My body has never been my own, merely a tool for others to wield as they see fit. It’s foreign to give it a second thought, or that someone might view it as more than a thing.
Sun-warmed fabric heats my hand as I grab my shorts off a nearby rock. “You came to my bath,” I argue as I slide them over my legs. “You are the pervert.”
Another shocked, barking laugh leaves him as he glances back at me to see my lower half covered. “Who taught you that word?” he demands.
I shrug as I pull on my shirt, unwilling to give up my source.
“It has to be Cameron or Elas,” he says, hiking his brow and waiting expectantly.
“You want me to speech English, yes?” I argue. “This means all the words.”
“Speak English,” he corrects, and I narrow my eyes again. “Yes, I want you to speak English because it will help you learn, but I also want to know who’s teaching you the colorful language.”
My brows pinch in the middle of my forehead. “Colorful? You teach me the colors.”
He makes that same frustrated scoff as he shakes his head. “No, the bad words.”
“Words are bad?”
“Yes, some are bad, like pervert. They’re rude, and saved for adult conversations.”
“I am not a child,” I argue as a rush of frustration mounts inside me. “You treat me that way. Always.” A familiar expression crosses his face—the soft one that tells me whatever he says next will be gentle because he’s afraid I’ll break.
Doesn’t he know I’m already broken?
A full month has passed since Elas and August returned from Ljómur, but I haven’t been able to bring myself to listen to their story. As they drove off, I was so sure I had sealed their fate. Encouraged them to go where no one should ever step foot, and to risk their lives inside the place that stole everything from me.
I was so terrified that I fled into the forest. For two days, I hid in the shadows, tucked away where I didn’t have to face what I’d done. Berries grew on a bush nearby, but eventually, they weren’t enough. The cramps in my stomach got worse until I could no longer ignore them.
