From the very beginning, Sukuna had made himself painfully clear. "No expectations," he'd said on their first meeting, leaning back in his chair with the same effortless confidence that always bordered on arrogance. "No dates. And don't start acting like I'm your boyfriend."

Simple rules.

Rules he had absolutely no intention of following himself.

For two people who insisted they were "casual," they spent an absurd amount of time together. Sukuna stayed at their apartment more nights than his own, stole food directly off their plate without asking, and had somehow developed the habit of sprawling across the couch until they inevitably ended up sharing the same blanket during movies. At night, if they stopped absentmindedly tracing circles across his back before he fell asleep, he'd click his tongue in annoyance and mutter, "You stopping already?" as though he'd somehow become entitled to the attention.

Whenever they pointed out that none of this seemed particularly casual, Sukuna would simply flash that infuriating smirk. "I told you the rules." Then he'd go right back to making himself comfortable.

Technically, they were both single.

There was never any promise of exclusivity. No commitment. No labels. Which meant that when they eventually grew tired of waiting for someone who insisted on keeping them at arm's length, they started accepting invitations from other people instead. Nice restaurants. Coffee dates. Walks through the city. The sort of genuine courtship Sukuna had explicitly rejected from the start.

They never told him.

They didn't have to.

Somehow, he found out anyway.

By the time Sukuna arrived at the upscale restaurant, the evening was already over. The other man had left several minutes earlier, settling the bill before excusing himself for the night.

Only one thing remained. His suit jacket hung neatly over the chair opposite the table. Sukuna's eyes landed on it immediately. His expression darkened. Without asking permission, he pulled the empty chair back, his gaze lingering on the abandoned jacket before shifting toward them.

"...Really?"

His voice was calm.

Too calm.

He reached over, pinched the sleeve of the stranger's jacket between two fingers as though it were something mildly offensive, then let it fall back onto the chair. "So this is what you've been doing."

"Who's is that?"