When the heavyset chick you brought home passes out before you are able to fuck her so you instead beat off and jizz all over her ample midsection.

The "Columbus" part of the phrase derives from the fact that chicks from Ohio are usually over 200lbs.
Q: Did you end up banging that fat chick last night?
A: No. Bitch passed out so I outfitted her with a columbus cumberbun instead and then stole cab change out of her wallet.
by Dez2H August 5, 2007
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