On hot days your ass and nuts start sweating, and some of your butt sauce begins migrating to your nutsack across your taint, causing irritation and general discomfort
A sex act in which a man has reverse cowgirl anal sex with a pregnant woman and in the middle of sex punches her in the stomach so hard she aborts the fetus then and there and drips said fetus onto the mans genitals.
Sally: Speaking of clinics I need to go to there and see if I'm charring, unless of course you wanna do the mustard dispenser ;)
An action in which one is eating a delicious sandwich with mustard overflowing from the sides, becomes sloppy and leans over the keyboard. Mustard then drips on to the keyboard and, while trying desperately to wipe it off, one will press too many keys and freeze the computer.
"I was talking with Sandy on msn last night while eating a sandwich, and I totally did a mustard malfunction!"