means the person saying it plans to seriously injure or kill the person it is said too
Tom: Hey, dude, you want to fight? Hit me!
Bill: Man, You should walk away! I have a black belt in karate. I will fuck you up!
by noladoc April 27, 2014
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I literally just engaged in sexual intercourse with you, but it was over so soon, you didn't enjoy it. Sorry.
Sorry, I just fucked you up. I'll do better next time. I promise.
by SadPancakes May 16, 2015
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