A penny is a girl who's two faced and likes to be in the back pocket. Normally, it's a girl calling another girl this, but a guy can also use this. If she's a penny, she is a two faced whore who likes it in the ass.
Damn! That bitch said that I was ugly behind my back. I'm still better looking than her ass! I don't give a fuck what she thinks because she's a useless penny. Bitch gets no Dick!