She got junk up in her trunk, I guess it's time to take out the trash
Junk in the trunk is used to say that the girl has a big and round butt.
Take out the trash is a phrase usually used in movies, where the good guy gives the bad guys what’s coming to them.
Chuckee takes both of these and combines them by saying that he’s going to beat her butt (with his junk).
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