Let's see . . . . boy, this'll be fun.

Byakuya : Hmm, Captain Ukitake, why have tou cut you hair so short? A form of rebellion to annoy Head Captain Yamamoto?
Shunsui : AAAAAAAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHAHA!!!!!!!!! WHAT HAPPENED TO CASANOVA? GOT TOO CLOSE TO SOMEONE'S BLADE?!?!
Yoruichi : ( is grinning even wider than usual ) Nice hair Ukitake. Are you trying to look like you're in the Academy again?

Toushiro : Hmph, weird old man. Is this some form of rebellion of some kind?
Kenpachi : HAHAHAHAHA!!!! Nice hair Ukitake. You goin' through a midlife crisis or somethin'?

Komamura : Oh . . . you look . . . . . very digified . . . Captain Ukitake. <----- Is too polite to say what he really thinks.
Mayuri : My my my Captain Ukitake, this isn't like you at all. Perhaps you're not feeling well if you did something this drastic to yourself.
Soi Fong : . . . . . . . . . . Whatever.
Renji :

Yumichika : Oh no no no Captain Ukitake. Your hair is supposed to be your crown of glory, and you go and cut it off? ( shakes his head )
Ikkkaku : Hey Captain Ukitake. Take a little more off and we'll be twins.
