((So… the song P.S. I Love You by Gackt was playing while I wrote this. It may or may not have influenced it. A lot. I'm sorry.))
Shunsui was waiting at the altar when the news came. They were supposed to get married. But then Rukia came, her little face pale and big eyes panicked.
"H-He's in the Fourth! Captain Unohana said you should come immediately… H-He collapsed while getting ready… It doesn't look good…" Her voice, normally so very strong, shook as she spoke. He hadn't heard her like this since Kaien had died.
—–
Unohana's face as grim when he arrived, even though he had used his fastest flash step. She shook her head as he got closer. "It's the end. He can't go for much longer… He has… An hour, at best. Go to him."
Shunsui could feel himself choking up, moving into the specified room. He sat down in the chair next to the bed, gently pushing the hair out of Juushiro's face. The other captain had a mask over his mouth and nose to help him breathe, but kept him from talking. Even with the mask, he could hear how Juushiro's breath seem to rattle inside his chest, and how difficult it was for him. He gently held his hand, being there and wanting to be there for every step of the way.
—–
He kept waiting by Juushiro's bedside, even long after his hand turned cold and his breathing had stopped. Long after they removed the mask, as it was no longer necessary. It wasn't until Yamamoto came to gently guide him away, that he moved.
"I don't understand. He was so healthy, just a few hours before…"
Unohana's smile was sad. "That is how it happens, sometimes. It could be that we just missed the warning signs of his worsening condition. There is nothing that we could have done, and you did nothing wrong."
Shunsui was grateful for the week Yamamoto gave him off to grieve. But he knew it would take centuries before he would truly be himself again.