A rat that has some how found its way in to your bum gap and has made babies..
They wiggle alot and cause some discomfort

You need to get them out by there kneck as if you grab the tail it will rip off
Dave: Some things wrigglying in my ass

Keith: You may have bum rats
by tomthebomb October 30, 2007
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a sneaky snitch with no redeaming qualities
a rat bum is like a junkie thief that will not gain anything to help themselves in the future
by mattie rolls November 25, 2008
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Someone who doesn't join the discord VC
Why is James being such a Bum Rat, just join the VC dammit
by klwpolar April 21, 2021
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Someone who doesnt join the Discord vc
Oh man why is James being such a Bum Rat
by klwpolar April 23, 2021
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