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Fat is just rude. Rats are disgusting. So Fat Rat goes fine together, but doesn't sound right. Therefore Fat Rat motherfucker just another level of Fat Fuck...just worse
Say your boss pisses you off to the point in which the word fat or fat fuck, just doesn't settle with you. Fat Rat Motherfucker is pretty insulting, personally i don't think anyone would like to be called a rat or fat rat either, so Fat Rat Motherfucker just makes it more fun to say.
by GodofGaming February 10, 2012
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