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When a person is born with the parts to form a butt (butt cheeks) but no flesh ever properly forms in it, so that the prson doesn't have the natural roundness of a butt and are therefore forced to sit on the extension of their thighs for lack of a natural butt. Or in simpler terms- lack of butt meat.
Hold on, is that Crystals's thighs or just her vestigial buttsack that's creeping from the top of her jeans when she bends over?
by Zoraya M May 19, 2008

Words related to vestigial buttsack

assless butt sack flat ass lack of butt meat no booty