Because Rufus is ascared of the dark, because when he was a kid his dad used to lock him in the cupboard so he could have saucy tea-parties with Hojo, Heidigger, Scarlett and professor Gast
And he has to do it himself because whenever he says "Oi Tseng come and screw in this..." tseng would always jump him before he could explain fully what he had meant.

who is better at syncronised swimming: Zack or Cloud?