What is Fuck It Up?
1.
To ruin something.Or go out and have a great time!!
Hey man if you dont take this new job serious you'll fuck it up!.Or Hey bro'congrats on your new job or engagement lets go out tonight and fuck it up.(party hard,Look for a fight. meet chicks.Get drunk etc..
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2.
to make somethign successful, or make it go your way.
Are you gonna fuck it up tonight? Hellz yeah...
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