The fact that se of you don't like Matt doesn't excuse how bad Gemma is acting. There's no excuse for her behaviour.
He has not egged her on, he has made it extremely clear how uncomfortable her sex talk makes him feel.
Sometimes, when men are being overly sexual and I don't like it, I might laugh or be nice to make it easier. But it doesn't mean I've encouraged it, sometimes we don't know how else to react when we're uncomfortable. Whereas I think Matt has been very consistent in showing he doesn't like it. Gemma has no respect.