A person who looks a complete mess most of the time but when it comes time for a party/ formal event etc. they turn up looking really hot.
"Dude Ryan looks good. He's shaved and put contacts in and everything."
"Yeah, he's a real doer-upper"

"Wow... is that Kate? Man she is a major doer-upper!"
by TheHastieLanyon June 4, 2014
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