The Master Key

I just had an argument with a girl I know. She was saying how that it's unfair that if a guy sleeps with a different girl every week, he's a legend, but if a girl sleeps with just two guys in a year, she's a prostitute.

So in response, I told her that if a key opens lots of locks, then it's a master key. But if a lock is opened by lots of keys, then it's a shitty lock.
That shut her up.