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to be reamed unknowingly, usualy from behind while still wearing ones underwear. resulting in undies being stuffed into the oriface in question
i gave that bitch from starbucks a rightious undie punch..
she was all like

"AWWWWWW i say stop that young man dont punch my underwear into my date"

"captain to the bridge, there has been a royal undie punching on the lower deck"
by reg the great October 02, 2007
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