a sexual act that may or may not be popular with trans women, according to Miranda Bellweather in Fucking Trans Women #0 muffing is the sexual act of penetrating one or both of the inguinal canals.

forcefully placing the female genitals over the mouth/nose.

A derogatory word used to describe simultaneous oral sex between two lesbians, often referred to as 69.

Muffing is the new Mudding - since iPhone decides to auto correct everything!

- giggles

To smell like one hasn't washed for a few months.

Long established Royal Navy slang for cunnilingus.
Alternative: Muff diving.

another use for fucked up