When a man gapes another man's asshole and then inserts a pocket pussy in his asshole and then has sex with the pocket pussy so that way it won't be gay.
I'm not gay or anything, but that dude is so hot I would give him a Shanghai Tunnel" or "Dude, if you don't knock it off I'm going to give you a Shanghai Tunnel"
by Jazzworth the Conqueror February 25, 2011
Adj. The act of inserting one's penis into a depleted toilet paper core and performing either vaginal or anal intercourse until the aforementioned core disintegrates with friction.
by Dr. Dyper (Reformed Sniper) August 27, 2016