To stick your finger into a friend's anus in an attempt to make him ejaculate so that you can have your turn.
When you're twos up on a girl and your mate is going on forever you might execute the Dirty Math.
When you're twos up on a girl and your mate is going on forever you might execute the Dirty Math.
Oh man I was having the best sex of my life with a filthy hookup last night until Phil pulled a Dirty Math on me. He couldn't wait to chow down on her creampie.
by No 1 in Japan June 19, 2020
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