When someone is giving you head and you fart.
Tom: "I totally gave Sarah a Mudd-Flapper last night."
Dave: "Dude, I did that to yer mom too!"
When someone farts, then immediately breaths in without realizing they have just breathed in there own fart gas, causing choking actions.
Tom: "Oh man, yesterday while trying to suck my own dick, I totally Hot-Lunged myself."
Dave: "Dude, what the fuck's wrong with you?"