A vagina that hasn't been touched till the penis has fully penetrated the (an) anus continously. For then the the vaginas will then become a stenchy dirty "Sewer-Cave".
"Dude she let me put it in her ass, THEN I f***** her one pussy!"
"Awe damn, did you eat her out afterwards?"
"He'll no, that shit was a Sewer Cave when I was done with it"
by The Douche Named Chad! July 1, 2015
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