A girl brings a guy home one night.
They get into her apartment and immediately she suggests that they do "69". "What the hell is that?" asks the guy.
Realizing he's inexperienced, she tries to explain, "I put my head between your legs and you put your head between mine."
Still not knowing what she's talking about, but not wanting to ruin the moment he agrees to try it.
The second they get in to the position, she lets go a RIP-ROARING fart.
"What was that for?" he asks.
Sorry, lets try it again." she says.
So, they get into position again, and once more she lets one loose.
The guy gets up and starts to put his coat on.
"Wait, where are you going?" she asks.
The guy says, "If you think I'm sticking around for 67 more of those, you're crazy!"