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When you have anal sex and stimulate the girl, a split second before she reaches her climax, you pull out and slap her as hard as you can on her loin causing the pain to be interpreted as pleasure by the brain and resulting in a total relaxation of the bladder and sphincter causing involuntary disposal of urine and feces.
She wanted such rough sex I buttbeam -ed her. We had to buy a new madras because I gave her a butt beam.
by Darlen April 05, 2010
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