Packing the clown car

Synonym for sexual intercourse, or the plans to engage in said activity

Layman's terms: Smashin' or trying to smash

Mark: Hey, where's Brandon?

Daniel: Oh, he's packing the clown car with Jenny.

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Rita: So, what are you doing tonight?

Bethany: Oh, me and Rodney are going to packing the clown car for the rest of the night.