When a couple are having anal sex and the man is pleasured with an unexpected residue when withdrawing from their partner's anus. The "unexpected residue" is brown in tint, and usually resembles algae..
Damn bro, I was humpin this chick in her ass, but when I pulled out she gave me some fucking brown algae on my rubber. FUCK that bitch needed to wash her ass out.
by MyExHasADirtyHole August 4, 2008
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