When your ass crack develops an insactiable appetite for your under wear. Both cheeks work together to devoure and clamp down hard, griping and embedding the under garment between both cheeks driving it towards the anus. Typically predominant in humid climates and a comon side effect of swamp butt.
Hey freind I have a bad case of clam butt, can you help fish my boxers out of my ass?

Look at the way that girl is walking, she must have a bad case of clam butt.

You should probably throw that underwear out after that bad case of clam butt you had.
by Fart splinters October 13, 2018
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