welltry and be friend with her and if you like her tell how you feel then if she breaks up with him there you go
If the girl has a boyfriend already,try not to get in the way. If she really does love you then she will break it off with her boyfriend. Don't try to rush her though as girls don't like that. Trust me, I am one.
It may be hard to do, but always talk to her... if she doesn't like you or doesn't feel right about the situation leave her alone and find someone better:D
give it a shot
A girl should be attracted to her boyfriend. Nothing 'happens' except that they love each other.
There shouldn't be a certain answer, it doesn't matter, what really matters is how much the boyfriend loves the girl
It really depends on what kind of person you are and what kind of person the boyfriend and other girl is. If you really trust your boyfriend then you should believe him but, if you aren't so sure about him and you trust the other girl then listen to her. But, like I said, it depends on the types of persons and it also depends on how much you trust these two. Its really your own call.
Treat her better than her boyfriend does.
she should really apologize and ezplain why she did that and eventuallly he will forgive her
Just like he does with anyone else, or he isn't really a good boyfriend!
lick her crotch
You can't.
There is nothing you can do if he has a girlfriend.Before making a move on him you should consider how you would feel if a girl did that to your boyfriend.