A guy starts talking to two women in a bar. They turn out to be Siamese twins, and they wind up back at his apartment. He fucks one, then starts to work on the other. He realizes that the first one is going to get bored, so he asks her what she’d like to do.
She says, “Is that a trombone in the corner? I’d love to play your trombone.”
So she plays it while he screws her sister.
A few weeks later the Siamese twins are walking past the guy’s apartment building. One of them says, “Let’s go up and see that guy we met.”
The other twin says, “Gee … do you think he will remember us?”