A sexual act where two people point there anuses towards each other, and one person poops in the other person's anushole. The receiving end then sucks in the poop using the reverse fart technique. Then the person who recieved then becomes the sender, and the sender becomes the reciever. This continues until one person's anus muscles become tired and cannot continue vacuuming.
by Urbandefinitions123454331 April 02, 2015
A rather cheap and/or crappie roadbike that was converted to a fixed gear, often with ghetto methods. Likely to have yates, and saddle set up at a slope angle
by lbb March 28, 2007
This person is a fucking idiot because A: this is retarded and B: ass to mouth is for when you're fucking a whore in the ass & slam your dick down her throat right after.
Methane isn't converted to carbon dioxide because CO2 is the byproduct of aerobic respiration, which involves OXYGYEN not METHANE you stupid ass fuck. ass to mouth conversion, ha.
by butt_dog November 16, 2006
when one farts into a his/her partners mouth, breaths it in, and thenceforth breathes it out, converting the methane into carbon dioxide.
by chuck July 29, 2003