Open the door slowly

You open the door slowly, not sure if your roommate might have already arrived. As you open the door you find to your surprise two young ladies standing on the bed giggling as they graffiti the walls with the words "drunk" and "old man".

They are cute; pretty redheads in tight white shorts that barely cover their tanned legs and loose tank-tops that mostly cover their upturned tits. You find the situation mildly amusing; a bit of destruction never hurt any one. Perhaps you could even use the spray-painted words as reminders of the hole you been in and the need not slip back into.

You could flip out and lose your temper, possibly ending up fired on your first day, or you could clear your throat and let them know you're there and see what happens.