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1.
Black Tuna, not to be confused with the Blackfin Tuna that swims in the vast Atlantic currents, is a term used to describe the raunchiest pussy out there. Usually worn out from constant coitus, the pussy develops a blackish hue and secrets an odor similar to that of a decaying tuna.
Me: Son of a bi*tch! What's that smell!?

Mom: That's your sister's "black tuna." We always knew she was a whore.
by Dong867 November 20, 2013