The sexual act of one sitting on their partners face with the anus covering their mouth, and passing as much gas as inside your body. The victims nose should be squeezed shut so he/she has to breathe it all in through their mouth. Also, some variations include the excrement of faeces into their mouth.
Husband: Shut up woman, and make me a sandwich, otherwise I'll Gas Chamber you later tonight, capiche?
Wife: Oh please no!