Punch him in the face, why bother to go on here and ask?
What do I do if my girlfriend got kissed by another guy forcefully?
Seriously ? Asking such a thing on here?
Man, if someone do that to my girlfriend no matter how much stronger or bigger they could be, the guy would be in hospital already.
Well "IF" it was forced .. then that depends on what option she prefers .. She can charge him with sexually assaulting her .. Or she can opt to put it behind her ... Not much YOU can do about it ... Unless you want to play the tough guy and confront him about it, and we all know where THAT would go.
I would have handled it at the time it was happening .. If someone were to do that to me, that was not welcomed .. A swift knee in the groin would probably change their mind about EVER doing that again.
Okay I get what a lot of people are saying, but going and beating this guy up will only land you in trouble. If your girlfriend wants to charge him with assult, support her, if she doesn't, support her in that as well.
If it happens in front of you, you yank his @$$ away from her and kick it. If it is after the fact, you ask her what she wants done. At the very least you let the guy know if it happens again with ANY girl, yours or not, you will take him down. Then follow through.
If he's troubling some more then go to the police or tell her parents. Telling parents about it might help!
YOU don't do anything it's up to your girlfriend to do something, she's not some Victorian lady she can let him know that if he ever touches her again in any way she will consider it assault and will go to the police.
He also owes her an apology,