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When two close males interact in a bonding experience in which they watch the same pornographic material and pleasure themselves at the same time. They do not have to be in the same room, but studies show the bond to be stronger when in the same location.
Me: "Hey buddy, do you wanna do a back-to-back Simon Threesome with me tonight?"

Griffin: "Would I ever!"

Me: "Sweet man! Don't forget a laptop, lotion, and tissues!"
by csemenmonster October 28, 2013
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