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
1 more definition
when one farts into a his/her partners mouth, breaths it in, and thenceforth breathes it out, converting the methane into carbon dioxide.
"I decided to try an ass to mouth voncersion while having my salad tossed by my gay lover, pierre.
by chuck July 28, 2003