Top definition. Sexual practice involving felatio immediately following anal sex, usually without cleaning off the penis first. Also known as "The Libby ". Ass to Mouth's arcane 2nd definition: when one is contacted by one means and replies by another.
Ass to mouth commonly abbreviated as A2M or ATM is a slang term primarily used to describe the withdrawal of an erect penis from the receptive partner's anus anal sex , followed by the immediate insertion into the receptive partner's mouth oral sex. Risk of STI or parasitic transmission exists generally only if fecal particulate from an infected person is transmitted to the mouth of an uninfected person. Porn industry performers often use enemas before filming anal sex sequences; however, this is primarily to eliminate the possibility of any fecal matter appearing on film rather than disease prevention. From Wikipedia, the free encyclopedia.