When a girl you are trying to hook up with/have sex with blocks you with her elbows (like a boxer blocking punches) so you can't cop a feel and she stops you when you try to stick your hand down her pants. She obviously won't spread her legs for you either. Usually everyone's clothes remain on and it ends up just being a long, wasted make-out session.
Friend A: I was trying to hook up with Jill the other night and it didn't work out so well.
Friend B: What happened?
Friend A: She high schooled me and nothing happened. It was a big waste of time.