UNEXPECTED OBSESSION- Sanzu Haruchiyo X OC Story

A Bonten Fanfiction

Sierra Ito doesn't believe in love-until she meets Haruchiyo Sanzu, Bonten's deranged right-hand man. Cold and ruthless, she built her empire, but him? He ignites something dangerous.

She denies it. Fights it. But love in their world is a death sentence.

"What would you do if nothing held you back?"

The first time she saw Sanzu, he was laughing-unhinged, wild, eyes burning like a predator's. She told herself it was disgust.

(It wasn't.)

His Obsession:
Sanzu's used to women who play with fire. Most die. But Sierra? She breathes it.

When he presses a gun to her head, she smiles.
When he does it again, she laughs.
By the third time, he's the one chasing her-and that pisses him off.

No one gets under his skin.
No one matters.

Yet the way she looks at him-like she sees every broken part of him-makes him want to ruin her... or keep her.

(He hasn't decided.)

Themes & Warnings:

🔥 Slow Burn - This isn't love at first sight. This is obsession, denial, and a battle of wills that neither of them can win.

💀 Violence & Gore - This is Bonten. Expect blood, torture, and morally bankrupt characters who kill without remorse.

🌑 Dark Romance - Sanzu isn't a hero. Sierra isn't a saint. Their love is twisted, possessive, and destructive.

🖤 Angst & Tragedy - "In another life, we'll meet again, and our story will be a happy ending." (But this isn't that life or maybe it is.)

💥 Smut - Of course. This is a Sanzu fanfic, after all.

Author's Note:

This is my first fanfic, and I'm obsessed with Sanzu. I've read every existing fic about him and still wanted more, so I decided to write my own.

Yes, it's cringe.
Yes, it's dark.
And yes, I have high hopes for this story.

If you have any plot suggestions, let me know!

(All characters belong to Ken Wakui except Sierra, Adi, and this plot.)

Hope you enjoy the descent into madness. 💖

|IMAGE CREDITS: PINTEREST ( I don't own any images used in the fic!)