The hypothetical device that over-made-up women must have used in order to apply the monstrous pile of caked-on colour to their face.
It refers to the Simpsons episode in which Homer invented such a device, which, after applied to his wife Marge, elicited the reply: "Homer! You've got it set on whore!"
Damn, girl, you look like a clown. Put down the make-up shotgun next time.
The hypothetical device used by oper-made-up-women to apply a thick, ugly layer of caked-on makeup to their faces. Refers to an episode of the Simpsons where Homer invented such a device, provoking the response; "Homer! You've got it set on whore!"
"Wow, Cindy really brought out the makeup shotgun this morning - she looks like a freaking clown."