I know that hooking up with a girl who has a boyfriend is bad.

 I go to the same gym as that girl and every single time she holds my hand and puts her hand on my lap. It has gotten to the point where we almost kissed.When she's in my class she does the same thing. 

Her boyfriend has always hated me, for some reason and I really couldn't care less. 

If I hook up with her it wouldn't be my fault since she is the one asking for it,right?