Kuchiki Byakuya could pinpoint the exact moment his current… arrangement… with Zaraki Kenpachi began.
Three days after Ichigo's departure from soul society, Byakuya was relaxing in the Fourth, waiting for Unohana to finally release him from her Division. She'd gotten smarter when it came to dealing with injured captains, and installed restraints on twelve beds that suppressed reiatsu. Now there wasn't anything they could do except wait.
The door opened, and Byakuya looked, hoping Unohana would let him go. To his surprise, Zaraki stood there.
"Pfft. Lazy nobles." Zaraki turned to go.
"Excuse me, peasant?"
Zaraki turned back around, smirking. "Yer one to talk, lettin' yourself be tied up like that."
It took a moment for that to sink in. "Letting? I'm not… did you find a way to break free?"
"Like I'd tell you."
"Arrogant jumped-up common son of—"
"Fight me?"
"Excuse me?"
"Fight me."
"I'm tied to this ridiculous contraption."
"I'll free ya if you agree to fight me."
It was Byakuya's turn to smirk. "It would be my pleasure."
Zaraki grinned, reached under the bed, and apparently did something, since the strap fell off. He unsheathed his Zanpakutou. "Might wanna grab yours."
"You want to fight here…"
"Yeah. Unohana's got Ikkaku healin' somewhere and won't let me find him. She's been mockin' me about bein' lost for hours. I wanna trash this place."
Kuchiki shrugged. He certainly wasn't happy about the restraints. He scattered Sebonzakura, wanting to beat Zaraki quickly in order to have time to escape Unohana.
Zaraki didn't dodge. Sebonzakura struck him, and he smiled, looking at the blood. "Not bad." Kenpachi pulled off his eyepatch. "My turn." He thrust forward, deliberately aiming for Byakuya's scarf.
Byakuya did dodge, turning and reaching out to touch Zaraki's shoulder. "Way of Bi—"
Kenpachi moved, faster than Byakuya thought he could, and slid his Zanpakutou along Byakuya's throat. "I could kill ya, because you're slow. But that wouldn't be any fun." He eyed Kuchiki, rather lewdly, to Byakuya's way of thinking. Zaraki slowly smiled.
A few minutes later, it wasn't just Byakuya who knew what Zaraki meant by the leer, but everyone in the Fourth Division, including Renji, who'd merely dropped by to check on his Captain. With that much reiatsu being released in the area, everyone knew.
Renji couldn't stop flinching at his Captain's gaze for weeks.