Perfume on a pig's ass

An attempt to mask a foul smell instead of actually dealing with the source of it, usually making it worse in the process. Most often referring to someone who tries using extra deodorant instead of actually showering on a regular basis.

Guy 1: Dude, you really need to shower before going out today.
Guy 2: Nah, we're in a hurry, I'll just put on some more deodorant.
Guy 1: You haven't showered in days. That'd just be perfume on a pig's ass. Get in the damn shower!