My girlfriend sent me a text saying that tomorrow at lunch shes going to sit on my lap?

Dude, is this seriously a problem? Why do you want to be scene anyway. If you could score a hot preppy chick, you could probably become "popular" if you wanted. But if that's not your forte, whatever. But if your scene buddies did make fun of you for it, you could just make fun of them for not having hot girlfriends to sit on their laps with. And I seriously doubt you'll cream in your pants, but if that's seriously a fear of you, then IDK, go ahead a j*** off to make you last longer with her on your lap lmfao