[Or at least for Pein. It's not even like he celebrates anything. Except for the day he becomes principal, in which he will celebrate with some fine whiskey and doing dirty dirty things to Konan.
But apart from that, he's back bright and early on a grey drizzling morning and writing out the next assignment for his students. In a good mood, because he loves nothing more then some work.
Hell, he's even got some music on. Disturb him at your peril.]