when a girl makes you cum when giving head or a handjob (although handjobs blow, and we can do a better job ourselves). Good girls always finish guys and swallow too, while mean girls leave the guys to finish themselves.
1) Man: "Ooooo. I'm gonna cum."
Mean girl: "Ok. Can we make out again?"
Man: "Why don't you finish me?"
Mean girl: "Gross."
2) Man: "Ooooo."
Good girl: "..."
Man: "I just busted one in the back of your throat."
Good girl: "I know. I liked it."