XD there's some moments sorta like that:
-When he's in disguise as Jeremy, he gets called an old guy and he gets insulted.
-In disguise on the Campania, Ciel calls him his father as a cover and he gets chibi-confused.
-In the S1 OVA, a kid in the audience calls him an old man and he gets insulted.
...Yknow, I think Sebastian's just in the denial stage of a mid-life crisis right now.

I know this is really random but I wanna see someone call Sebastian an old man or smth because of his age and Sebastian getting very insulted by it like "EXCUSE ME? ! " (づ ̄ ³ ̄)づ im weird