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When a girl got a fatass and you got to stop and reevaluate your whole life.
Damn, that girl's got a fucking muscle butt!
by Rams03 May 27, 2016
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2
A girl who has a ass that is so muscular that if she wasn't muscular it would be straight flat
Damn maddys ass is so muscular she got a muscle butt
by David Yeum May 16, 2016
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