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When a guy takes his hard dick, after having anal sex and swings it as hard as he can, hitting a person (hopefully a girl) on her cheek with his penis. If done correctly it will leave a mushroom imprint for several minutes with a lasting red spot afterwards and a nice brown mushroom stain.
That stupid bitch pissed me off so I stuck it in her ass and then gave her a nice Dirty Mushroom
by zack dazuk July 06, 2011