Refers to a cute girl who's body looks good in clothes but awful naked.
For example, when you crack an uncooked egg into a pan, the whites and yolks go everywhere you don't want them to go. You want the yolk in the middle, but it just keeps running all over. A girl is an uncooked egg if you think her lady bits will go all over the second her clothes come off.
Guy 1: I can't tell if I'd bang her or not...sometimes she looks real good.
Guy 2: Don't waste your time bro, she's a total uncooked egg.
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