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When you are fucking a girl, you pull your boner out, bend it in half and shove it back in. Upon being pulled out, the boner is purple like a plumb and stinks like an onion.
1. Shit man.... shit..... that is one plumb onion!

2. You ain't gettin' none o this vajayjay unless I get somma that plumb onion!

3. My plumb onion hurts real bad!

4. Dr.: "Don't bend your penis in half like that anymore."
Patient: "But my girl wants the plumb onion real bad."
Dr.: "Oh, here are some pills."
by Prof. Plumb January 03, 2008
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