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Whether you’re here for forbidden flings, found family feels, or the kind of tension that leaves you breathless - this is where it all begins.

ROMANCE THAT PACKS A PUNCH
newest release

Revive Me

An injury that changed everything. A man who’s angry at the world. A woman who won't let him give up.

Once, Roman was a professional MMA fighter on the brink of becoming the best in the world. But when an injury to his spinal cord alters the trajectory of his life, he not only has to learn how to walk again, he also needs to rediscover who he is with the disability that shattered his dreams. And he has to do it with the help of the first person to make him hope again—and the one woman he can’t have.

When Roman enters the physical therapy clinic, defeated and unmotivated, it's clear to Liliana that a tough love approach is going to be the only way to help him heal, both physically and emotionally. But it doesn't take long until that desire to help extends beyond her professional responsibility and grows into something much deeper.

THE SERIES THAT STARTED it all

The Fight Game

Alpha MMA heroes, fierce heroines, and emotional knockouts you’ll feel in your chest. Dive into the bestselling series that started the chaos.

THE FIGHT GAME | BOOK ONE

5 Rounds: An Enemies to Lovers Sports Romance 

She's a feisty workaholic that hates his guts. He's an arrogant MMA fighter that can't afford any distractions. This isn't the kind of fight they're used to...

When Remy is suddenly evicted from her apartment, her best friend offers to let her crash at his house while he's traveling for work. The only problem is, she can't stand his arrogant, self-centered roommate, Tristan.

Now, she has to figure out how to live in the same house with him for ten days while dealing with all the temptation that comes with… including punching Tristan’s smug face in. But when one night strips them of their masks and exposes the truth, they’re forced to reexamine how they really feel about each other...

Can Tristan and Remy drop their guards long enough to fall in love? Or will old prejudices deliver the final blow?

"5 Rounds" is book #1 in the Fight Game series but can be read as a standalone.

THE FIGHT GAME | BOOK TWO

2 Fights: A Friends to Lovers Sports Romance

A toxic ex. A girl who lost herself. A childhood friend helping her find the way back.

When Hailey finally ends her relationship with her narcissistic ex-boyfriend, she thinks all her troubles have ended. But what she doesn’t realize is that the wounds he inflicted aren’t on her skin, but in the way she sees herself. And the only person capable of helping her heal has been in her corner all her life.

Jax has had a soft spot for the younger Porter sister ever since his family moved into their neighborhood. It feels like the most natural thing in the world to go from helping her with math homework, to holding her hand through a rough breakup years later. But as he starts to show her how beautiful and worthy she already is, he himself starts to notice the incredible woman that she grew up to be.

Can Jax and Hailey start something new while the past is hovering over their heads? Or will Hailey’s scars hurt them both?

"2 Fights" is book #2 in the Fight Game series but can be read as a standalone.

THE FIGHT GAME | BOOK THREE

3 Count: A Friends with Benefits to Lovers Sports Romance 

A charming ladies' man that everybody loves. A badass photojournalist that treats every day as a new adventure. A friends with benefits relationship.

When Aiden and Dani meet on his college campus, their playful banter and physical chemistry immediately draw them to each other. It's easy for one accidental meet-cute to become a standing date, and for a certain understanding to develop between them. Because neither one of them has any interest in anything serious.

Over time, their physical relationship blossoms into an actual friendship. Before long, they're texting for no reason, meeting each other's friends, and spending nights together that don't end between the sheets. But the closer they get, the more both of their apprehension toward relationships becomes an obstacle between them.

Will Aiden and Dani be able to get past their relationship fears and let themselves fall in love? Or will their mistrust of love keep them from their happy ending?

"3 Count" is book #3 in the Fight Game series but can be read as a standalone.

THE FIGHT GAME | BOOK FOUR

1 Last Shot: An Opposites Attract Sports Romance

He's running from his past. She's searching for a new future. Their journeys are about to collide.

When an injury overturns her ballet career, Isabella decides to move to a new city so she can start fresh and discover who she is without dance. The last person she expects to meet is the angry MMA fighter living next door.

Kane has spent his entire life putting up walls to keep people out, and he's never had any problem doing it—until Isabella. Because the second the sweet ballerina appears in his life, it becomes apparent that his short fuse and brazen rudeness are not going to be enough to keep her away. And suddenly, that doesn't seem like the worst thing in the world.

While Isabella searches for a new identity for herself, Kane has to decide if he's willing to take a chance on someone for the first time in his life.

Can Kane and Isabella help each other to find their new paths in life? Or will Kane's ugly past keep them from their happy ending?

"1 Last Shot" is book #4 in the Fight Game series but can be read as a standalone.

THE FIGHT GAME | BOOK FIVE

4th Degree: An Age Gap Sports Romance

He's her coach. She's too young. They're both risking everything.

Forced to grow up too soon, Skylar has built her entire life around taking care of her family. But when she catches her first lucky break, she’s finally able to pick up the sport that has always intrigued her. Signing up at the local MMA gym is where she meets Coach Dominic.

Because everything in Dominic’s life is based on his reputation as a coach and fighter, he’s always kept a professional boundary between himself and his students. But when Skylar impresses him in the gym, and their post-class chats start to last into the night, that boundary begins to blur. Before long, a relationship develops between them—that they’re forced to keep behind closed doors.

While Skylar struggles to balance her feelings for Dominic with taking care of her family, Dominic has to decide if he’s willing to risk everything for a chance at love.

Will Dominic and Skylar let themselves find happiness with each other? Or is the cost of their relationship too high?

"4th Degree" is book #5 in the Fight Game series but can be read as a standalone.

looking for a quick, spicy read?

Just Tonight Novellas

Short, spicy standalones with all the Nikki Castle heat and heart - perfect for when you want your next book boyfriend now.

The Stranger in Seat 8B: A Reverse Grumpy/Sunshine Novella

He has one rule on flights… No working in the air. And he's determined to make the ice queen abide by it.

Annie is a workaholic. Her entire life revolves around being a successful lawyer, which means she has no time for anything or anyone else. And that includes engaging with handsome strangers that try to distract her from working.

Damien knows the second he sits beside her that he's going to ignore the unspoken flight etiquette that says not to initiate small talk. He can’t help but to coax Annie out of her cold shell, one playful comment at a time.

Can Damien convince Annie to take a chance on him, even if it's just for tonight? Or will she rebuild her walls and shut him out?

"The Stranger in Seat 8B" is a complete standalone novella.

The Waiter at Table 6: A Reverse Age Gap Novella 

She has too much baggage. They've lived entirely different lives. None of that is stopping him from wanting her.

Recently divorced, Vanessa moves into the beach house she won in the settlement. After spending years in a marriage that took her identity, she hopes a new environment will help her rediscover who she is. And then she meets Ryder.

Ryder is young, full of life, and knows exactly who he is—and what he wants. And even when Vanessa puts the brakes on their relationship after one night together, he's still happy to support her in the form of friendship, taking any excuse to spend time with her.

Can Ryder show Vanessa what a healthy relationship looks like? Or will her past scare Vanessa into a lonely life?

"The Waiter at Table 6" is a complete standalone novella.

FREE SHORT STORY

The Tinder Fix

What happens when a no-nonsense bartender and a dating app disaster collide?

Chaos, banter, and the kind of chemistry that turns a bad date into a very good story. This standalone short delivers Nikki’s signature mix of humor, heart, and heat - all in one bite-sized read. If you’re between books (or just need a quick Nikki fix), this is for you.

"The Tinder Fix" is a short story only available on this website as an ebook. It cannot be purchased as a paperback anywhere.

and coming soon...

The Price Brothers

An interconnected standalone series about three brothers who find love in the most unsuspecting places.

Book 1 coming February 2026!

Upcoming release

Love for Hire

An MMA fighter x escort romance

"Love for Hire" is book one in a brand new series! Coming February 23, 2026 in all formats. Preorder the ebook at a discount today!

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Ends February 23, 2026 at 12:00 am
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WHAT READERS ARE SAYING
WHAT READERS ARE SAYING
"There’s nothing better than a well-written enemies-to-lovers story where the sexual tension just drips from the page. Throw in the physical and mental strength of MMA fighting, reluctant roommates, and a love-hate that has been brewing for years and you get the explosive heat that is Tristan & Remy."
— 5 ROUNDS | Amazon Review
WHAT READERS ARE SAYING
"This story packed SO MUCH into a small, 100 page package. I loved the pacing of it and how Damien and Annie matched each other so very perfectly. I have nothing bad to say about this novella other than I wish it was longer so we could get more of them. Overall LOVED THIS and if you are looking for something quick to read in an afternoon, look no further!!"
— THE STRANGER IN SEAT 8B | Amazon Review
WHAT READERS ARE SAYING
"This book isn’t just a sports romance—it’s about healing, finding purpose, and letting someone in when you least expect it. If you love grumpy/sunshine dynamics, aching slow burns, and characters who fight for their second chance, Revive Me will absolutely own you."
— Revive Me | Amazon Review