The act of taking a shit and piss on your partner's chest and then sliding through it and splashing it on their face like the Pittsburgh Plunge ride at Kennywood. Also similar to a Slip N Slide.
Dan: "Hey Rose do you want to try the Pittsburgh Plunge?!"

Rose: "Sure! I hope you have diarreah so its extra slippery!"
by GoPens June 13, 2009
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