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1.
Anal sex of the variety during which the penetrating participant experiences an unpleasant sensation of coarseness or friction, usually owing to the receiving partner's having a bad case of dirty butt. Grainal sex is definitively disappointing, and typically leaves the receiving partner in discomfort or pain, while the giving partner will find himself with a bad case of poop dick.
It wasn't as great as I hoped it would be. After we were done, she was over there cryin' and my dick smelled like shit.. it was really grainal.
by The War Room December 10, 2010