(Note: this takes place a little while after the Seireitei arc)
Byakuya stood outside of the 4th Company office, watching as various members walked in and out. It was nearing nighttime, and soon everyone would be gone.
He'd been waiting for a while – nearly an hour. His legs were getting stiff, but he'd made up his mind and he wasn't leaving until he'd said his peace, and that was final. He turned when he saw someone peeking out the door, staring at him. As soon as he looked they closed the door, disappearing from sight. Byakuya sighed and shifted, trying to get his legs to un-cramp. It shouldn't be much longer...
Isane jumped back in Unohana's office, slamming the door. Unohana glanced up at her assistant captain. "Well?" Isane leaned against the door. "He's still there. What do you think he's doing, Captain?" Unohana straightened a stack of papers and started on a second. "He must be waiting for someone." Isane stole another quick peek, making sure not to be caught again. "I wonder who..."
The sun had finally began to set and Isane had gone home, bidding her captain good night. Byakuya watched her go, making sure that no one was around. Taking a last glance to ensure his presence was not betrayed he opened the door and slid in quietly.
Unohana had just been preparing to leave when the door opened again, after having just been closed. Her back was turned, but she recognized the visitor immediately. "Good evening, Kuchiki-taichou. Is there something I can help you with?" Byakuya took a step forward as she faced him. She was surprised to see that there was a bit of apprehension in his features. "Kuchiki-taichou?" He made a point to look straight at her, focusing on her eyes. "I have made an error." She seemed confused. "An error, Kuchiki-taichou?"
He nodded solemnly, as if he were giving bad news to a dying man's family. "Yes. It seems I have forgotten to thank you." If Unohana had been confused before, now she was totally lost. "Thank me? For what?" He was closer than he had been before, so close she could smell the scent of his cologne – it was sandalwood and something almost musky. He stared down into her heart-shaped face, and she swore she saw him shudder. "For treating my injuries of late. Thanks to your care, they have left not a single scar." Unohana decided that Byakuya's voice was the smoothest she'd ever heard.
She smiled gently and a pale hand fluttered up to her chest. "Kuchiki-taichou, it is my duty to heal, but I am pleased to hear that you are happy with your recovery. I was also glad to know that you had healed completely." Byakuya decided that Unohana's smile was the most beautiful he'd ever seen.
Now Byakuya was so close that he was touching her, their chests brushing gently. "You are modest. That is admirable." Now his face was approaching hers and his skin was fair and unlined. "But you see, Unohana-taichou, I am determined to thank you." He was totally against her, and she shivered when his thin arm slipped around her waist. She was about to protest, but with a whisper of cloth in the dark and the beat of a heart his lips were on hers and he was holding her so terribly close, kissing her with a passion he'd forgotten he'd possessed.
After a few moments of sweet union he released her. They remained together loosely, his arm still draped above her waist. He gave her the faintest of smiles.
"Thank you. Retsu."
And then he was gone. A rush of black and white and her office was empty again, occupied by naught but her and her fiercely beating heart. Minutes dragged on quietly, and when her breath came evenly again, Unohana placed her fingers to her lips, and smiled a little, too.
"You're welcome. Byakuya."