BEYOND//UNDERGROUND: a dark obsession romance, beyond underground

by Lilly Chase

OBSESSION. LUST. A SECRET THAT WAITS 400 ft BENEATH THE SURFACE.

Suddenly, my life became consumed by obsessive stalking, dark lust, dangerous jealousy, underground hacking, illegal technology and people around me disappearing.

Jim was a fucked-up and cold tech billionaire, determined to destroy himself with drugs and insomnia while playing with power and people's lives like chess pieces. And he carried a vile secret far beyond anything a human mind could ever picture.

I am Lilly. A virgin, a broke art student working two jobs and a painfully average girl.
The closer I got to him, the more my traumatic past tore open and things only got more complicated when his older brother appeared. I met people who became the family I never dared to dream about. But I also constantly questioned who I could trust.
I never thought I could find myself in the darkest places. But when I finally collided with his world, I did. Beyond him. Beyond me.
Beyond Underground.

BEYOND//UNDERGROUND is an immersive dark romance and psychological thriller built around a story that doesn't end on the last page. The novel opens into a larger universe of interconnected characters, hidden lore and experiences that continue beyond the book.

Genres: Dark Romance

701 pages, Kindle Edition

Published October 18, 2026

About the author

I’m the author, artist and creator behind the BEYOND//UNDERGROUND universe.

I write immersive psychological erotic fiction about obsession, trauma, technology, human darkness and the strange places we sometimes find home in between it all.

BEYOND//UNDERGROUND is only the beginning of my story and will grow into an ongoing series. But my stories don’t end on the last page. They open into a much bigger universe.

Dive deeper into the world you entered through the story.

Keep living in it and meet the characters, uncover detailed hidden lore, like the music and places and explore the universe through interactive games, events and more.

Within my world, you’ll find a community that feels like family.

This universe is alive, and it holds a place for you, no matter how dark or different you think you are.

Welcome to my world.

Welcome to the Underground

Reviews

[Chloe Flockhart · Rating 5 out of 5]

I need more people to read this book!💖🖤

One of my favourite things about Beyond Underground is the descriptive writing. It’s immersive in a way that’s difficult to put into words. This isn’t the kind of overly descriptive writing that adds nothing to the story or makes you want to skim paragraphs. Every detail feels intentional. You don’t just read what’s happening; you can almost see it, hear it, feel it. It draws you so deeply into the story that you feel like you’re experiencing it rather than simply reading it, I feel, even though it is written from the FMC POV, the intentional way things are structured makes it feel like the MMC is bleeding through. The 🌶️ is great, some of it intense, but it’s not spice for spice sake, for me, it served a purpose in the story telling.

Throughout the book, there are QR codes that take you directly to songs selected for specific sections of the story. The music isn’t just a playlist thrown at you before you start reading; it’s incorporated throughout the book at the moments the author wants you to experience it. I absolutely LOVE this. Combined with the descriptive writing, it adds another layer to the atmosphere and makes the reading experience feel so much more immersive

The mystery is another thing I loved. The unanswered questions never felt frustrating because I was so invested in the world and the story itself. And when the secret is finally revealed, rather than feeling like everything has fallen into place, you suddenly realise there’s so much more you need to understand. I finished this book with even more questions and anticipation than I started with, and I desperately need to know more about the Underground.

What I loved most about this book is that it doesn’t rely on one big reveal to keep you interested. The atmosphere, the writing, the mystery and the entire reading experience work together to pull you in and keep you there.

I went into this book not knowing what to expect, and I came out completely invested in a world I’m nowhere near ready to leave.

Please, if you’re looking for something that feels different from your usual reading experience, give this book a chance. I genuinely think it deserves so much love and recognition. 💖🖤

[Ceri Powell · Rating 5 out of 5]

I'm not even going to pretend I didn't absolutely LOVE this book.
Jim's obsession with Lilly had me completely hooked. The intensity, the fixation, the way he couldn't seem to get her out of his head I was obsessed with their dynamic. 🥀🖤
But what made this story hit differently for me was Lilly herself. Being constantly told you're oversensitive, that you feel too much or that you take things too much to heart, can really get into your head. I related to Lilly on a level I wasn't expecting, and that made her character feel so much more personal to me. Lilly is a breathe of fresh air.

Sometimes you read a book for the dark romance, but end up finding a character who makes you feel a little less alone in the way you experience the world.
Jim's obsession had me hooked and of course he has flaws but all of our favourite mmc's do thats why we love them.
seeing parts of myself in Lilly made this book special.
10/10 obsession
10/10 emotional connection
This book will always stay with me 🖤

I related to Lilly because I know what it's like to be made to feel like your emotions are a flaw. Maybe we're not too sensitive. Maybe we just feel things more deeply than some people know how to understand and that's okay 🖤

[Skye Olivia · Rating 5 out of 5]

This book is devastatingly incredible 🚨

You don’t just read this book, you live it! You feel every second of it! You become part of the underground!!

This is my top read of 2026 & quite possibly the best book I’ve ever read ‼️

If you’re ready for a book that will have you questioning everything, have your mind spiralling, have your heart breaking, have new emotions unlocking, have confusion wrapped around your mind & have your legs kicking & screaming…then this is your sign to PICK UP THIS BOOK IMMEDIATELY ❤️‍🔥

Lilly Chase your work is what they call Chefs Kiss 💋

[Merissa · Rating 5 out of 5]

Lilly reached out to me and asked if I’d be interested in reading her book. Let’s just say, the moment she told me it had 104 TW’s, it was an automatic ABSOLUTELY!! 😂🖤

First off, the COVER?! The cover alone had me intrigued. The amount of thought and detail Lilly put into designing it says so much about her as an author. I love when you can tell an author has poured their heart into every little detail of their book.

Now, let’s get into the actual story. 👀

One thing I absolutely LOVED was how descriptive Lilly's writing was. She has a way of bringing every little detail to life without making it feel overwhelming. Normally, with bigger books like this, you tend to run into a lot of unnecessary filler, but I honestly didn't feel that way with this one.

The mystery surrounding Jim, Hendric, and honestly, the entire crew had me HOOKED. I needed answers, and I needed them ASAP. One minute I was on page 124, and the next thing I knew, I was on page 567. HOW?! I genuinely didn't want to put this book down because I HAD to know what the hell was going on!

I would definitely consider this a slow burn, but BABYYYY, when that spice finally hit?! HOT AF!

Something I really appreciated about this book is that it isn't your typical dark romance where 100 different trigger warnings are crammed into 300 pages or less. Don't get me wrong, I love my unhinged, pitch-black reads, but this one was DIFFERENT. It has an actual well-developed storyline, layers of mystery, and characters that keep you questioning EVERYTHING.

There were even moments when I caught myself wondering, "Wait a damn minute... is this based on something Lilly actually experienced IRL?!" Because if so, that would be WILD AF!

Overall, I'm SO glad Lilly reached out and put this book on my radar. This is exactly why I love discovering and supporting indie authors. Sometimes you come across a book you probably wouldn't have found on your own, and it ends up completely surprising you.

If you're someone who enjoys dark, twisted reads with a well-developed plot, mystery, slow-burn tension, and some seriously HOT spice, I definitely recommend checking this one out!

104 TW’s, and now I'm impatiently waiting for BOOK TWO!

Thank you, Lilly, for trusting me with your book! I can't wait to see where this story goes next! 🖤📖