When a girl uses her boobs to pleasure a guy. A girl doesn’t need to have big boobs to do it, but in order to do it porn style she needs to be at least a d cup.
Dude 1: That’s your girlfriend? But she’s fat.
Dude 2: So?
Dude 1: She must weigh more than you.
Dude 2: She has a pretty face and gives me titty sex though.