Either dark, scabby cuts on a person's ass. (usually, find out during $3x)
or
The perfect cookness of a marshmellow(between burnt and golden brown)
Jeff: When i was with veronica, yo her ass was pimplin brown

Jim: Awwwee, siiiick...

or

Nick: look, look...

Owen: what... ohh hot damn your marshmellow is pimplin brown..

Nick: ya i know its perfect...
by Samm Semaj Kcin December 1, 2010
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