When two people rub there privates together while wearing there underwear.
Chad : How bout you ride Chad's cock after work babe!
Kiersten : Sorry I'm on my period I would rather avoid the mess!
Chad : But I need to clean the pipes I guess i'll jack off tonight!
Kiersten : Hey how about A Undie Rub I know that would make you cum?
Chad : Sure i'll bring some extra underwear!
by SlopNChop March 24, 2017
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