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You catch a fresh fish, (with salt water and everything) still on it and immediately smother it with nacho cheese, thus, filling up the gills with nacho cheese. This taste is supposed to resemble the taste of a dirty asshole.
Nick: Hey Mark, so i was licking my girlfriends butthole, and it tasted like Fishy Butthole!

Mark: Dude........nasty.
by KidsPoopInMYLunchBox January 06, 2010
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