The guncky build-up underneath the flap of skin on an un-cercumcized cock.
Girl: That boy got duct butter in my vagina.
by Rickifer July 4, 2006
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The shit that pours out of a broads pussy after your done fucking her. A mixture of her pussy juice and your cum
Man, after I finshed fucking this bitch she left Duct Butter all over my back seat.
by Fredz November 1, 2006
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