While penetrating a girl in the ass, you place a saxophone (or similar instrument) in her vagina, thus double penetrating her. Upon reaching climax you pull out of her, and cum in the bell end of the saxophone. You then take the saxophone, place it in your mouth with the bell up to the girl's face. Then you blow very hard on the instrument, so that the semen flies out of it onto the girl.
I'm crazy, I gave this girl a Dixie Duet last night.