When you perform cunnilingus on a girl while she is taking a shit. It involves the use by a sex partner of the mouth, lips and tongue to stimulate the female's clitoris and vulva while she is making a poo. The lesbian blumpkin.
"Maybe going dumper diving on Rhonda in the Taco Bell bathroom wasn't such a good idea" Bro#1 (hipster with beard)

"Bro, I bet you were a hot mess!" Bro#2

"Bro, you can say that again!"Bro#1
by Cherryrainbow August 16, 2011
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