Not really an RP lesson, but something tells me you'll like this story.

In New Orleans. At a club. Hot girls running around selling test tube shots out of racks.

Girl: Buy me a shot. (Yea, not asking, but telling me)

Me: No.

Girl: Come on, buy me a shot.

Me: You're not my girlfriend.

Girl: I could be tonight.

Me: Once girls start calling themselves my girlfriend, they stop having sex with me.

Girl looks pouty, walks away. I'm still giggling.