Tilting her head curiously at Ichigo's approach, Rukia watches with wide eyes up until the point his path seems to shift, leading him back to his chair, where he sits down with a heavy slump. It startles her, if perhaps in no meaningful way, blinking in his wake before quickly coming back to her senses and getting out a knife for cutting the cake. And even that's a dilemma in of itself — does he want to cut the cake? Should she? She's unfamiliar with modern etiquette when it comes to such things.

"Birthdays don't have quite as much pomp and fanfare on an annual basis," Rukia replies thoughtfully, deciding to wordlessly turn the knife around and offer the handle to Ichigo with a raised brow. "Big milestones are still important, of course. I don't really remember mine, but I chose January fourteenth to mark the passing of the years." The more sobering implications, she doesn't quite bring to light. Ichigo knows them already. She's bound to live a far longer life than most humans ever could.

Ichigo being a possible exception.