A sex move from the scat fetish category.

First, you bend the girl over and fuck her in the ass. Then you turn around, spread her cheeks and yours and take a good sized shit right into her buttcrack. Then you need to turn around and literally pound your own shit into her ass.
Kelly called the cops on Bill because he did the Fudge Piston on her.
by EMOGRILL August 4, 2008
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