The Red Diamonds aren’t just a mafia — they’re a family built in blood, loyalty, and quiet understanding.

At the center stands Choi San, the level-headed leader who believes judgment comes before execution. At his side is his husband, Wooyoung, softer in tone but just as sharp, balancing San’s control with warmth that keeps the group human.

Their strongest weapon is Hwang Hyunjin — San’s greatest creation. Cold. Silent. A man whose stare alone makes people unravel. He doesn’t waste words, doesn’t waste mercy, and doesn’t hesitate.

The rest — Bambam, Jihyun, Ryujin, Soohyun, and Sunoo — form the core of Red Diamonds. Skilled. Loyal. Deadly when needed.

And then there’s Kim Seungmin.

Not a member. Not a stranger.

Hyunjin’s nemesis. His opposite. His unfinished sentence.

Seungmin operates alone, appearing only when things spiral beyond control. He and Hyunjin clash like fire and steel, yet whenever Red Diamonds face true danger…

Seungmin shows up.

Uninvited. Unbothered. Unexplainable.

No one knows whose side he’s truly on.

Maybe not even Hyunjin.

⸻

13th floor.

The hallway reeked of gunpowder and shattered drywall.

Red Diamonds stood spread out, backs nearly aligned out of instinct rather than command. San was calm, calculating. Wooyoung’s eyes tracked every movement. Ryujin reloaded smoothly. Bambam and Sunoo covered the flank. Jihyun and Soohyun watched the stairwell.

And at the front —

Hyunjin.

Still. Silent. Terrifying.

The rival gang circled, weapons drawn, numbers too high.

San exhaled. “We push left. Fast.”

It erupted.

Gunshots. Shouting. Glass breaking. Bodies hitting the ground. Wooyoung moved with precise strikes. Ryujin didn’t miss. Bambam laughed under his breath like this was routine.

Hyunjin didn’t rush.

He walked.

Each step meant someone dropped.

But they kept coming.

Then—

CRASH.

A body slammed into the large hallway window.

The glass splintered.

A second later it completely exploded outward, shards raining down into the night.

Silence fell for half a second.

Too quiet.

San frowned. “That’s not us.”

Hyunjin stepped toward the broken window, gaze lowering.

The others followed.

13 floors down, in the glow of streetlights and scattered headlights…

Bodies.

Their rival’s backup team.

All down.

All motionless.

Standing in the middle of them like he’d just walked into a café—

Kim Seungmin.

One hand in his pocket.

The other holding an iced americano.

He took a slow sip.

Looked up.

Met Hyunjin’s eyes from 13 floors below.

Then he lifted his hand and gave a lazy, almost polite little wave.

A smirk tugged at his lips.

Wooyoung blinked. “…You’ve got to be kidding me.”

Bambam let out a breath. “He beat us to it.”

San glanced at Hyunjin. “Your problem?”

Hyunjin didn’t answer.

Didn’t move.

But his eyes sharpened — not with anger.

Recognition.

Seungmin tilted his head, like What? You needed help.

Hyunjin finally spoke, voice low, unreadable.

“…Tch.”

Down below, Seungmin mouthed something.

Hyunjin knew exactly what it was.

You’re welcome.

And just like that, Seungmin turned, stepping over bodies casually, sipping his drink as if he hadn’t just wiped out an entire squad alone.

San sighed. “One day, you’re going to explain him.”