When a guy puts a paper bag on a girl's head to cover her ugly face during intercourse. This is done when the guy finds the girl's face unattractive but wants to have sex with her. Holes are put into the bag so that the girl can still breathe. Sometimes a hole will be made so that the girl can give the guy a blowjob.
Dude1: Man that chick is ugly!
Dude2: Yeah but look at her ass! I would bag her.