theres a guy at college who is so pervy it makes me sick. he constantly spanks my girlfriend as he walks past, or tries to undo her bra etc. but she just thinks its a joke and isnt really bothered by it. me on the other hand, i cant stand it and it really [censored] me off.

well today he decided to spit a mouthful of water at her (he said in a jokey way), and to make it worse everyone just laughed as if it was something funny. this guy is really beginning to bug me now, and i really want to beat the crap outta him to be honest. but i know you guys are going to say thats not what i should be doing. so my question is, what do i do?