A Dirty Duff is a sex move inspired by the great Garrett Duffy, the most badass baseball pitcher to ever play for Red Mountain High School. A Dirty Duff is a signature move in which the male shoves a baseball bat into the woman's vagina and then proceeds to throw batting practice to the girl, the girl will swing the bat using the muscles in her pussy and clitoris and hit the ball.This is really a revolutionary form of exercise and can be very beneficial for the woman as it strengthens her pussy muscles and mental toughness. Using this move you really can hit a homerun, no pun intended.
Guy 1:"I saw you leaving school with Mackenzie the other day."

Guy 2: " You know I took her straight home and gave her that Dirty Duff."

Mackenzie:*squirt squirt squirt*
by RMHS Unknown Nigga December 10, 2013
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