Luxuria
Neither of them are sure how they got to this point; why they are still doing... this. It seemed a game to begin with, a double dare to see who would back down first. But now his hand is sliding up and under her skirt and she is rubbing against him and keening for more like a bitch on heat, and oh fuck it he's going to hell anyway, so little Miss Perfect Trinket may as well be dragged down with him.
He should not be enjoying this and she's certainly not meant to be such a willing a participant. As he thrusts himself into her; so tight, so wet, so wrong, he wonders to himself - why then, does this feel so... right?