A woman who has put on a few pounds since the last time that a random72 year old Uncle will say to Larry, the cousin twice removed, this kind of thing:
Uncle: "Golly! That's Suzanne? She has gotten to be a real Plump Sister since the last time I saw her."
Larry: "Must've been back in the Seventies. Before the kid. Kids. Who knows."
Uncle: "It was May 1979. When they got married...wow she just blimped out!" Larry: "Total butterball. Plump Sister, shame."
A pomp-hole is short for a person being a pompous asshole. This type of person is of the Gordon Gekko, Patrick Bateman, or Regina George (mean girls) mold. Though all of the aforementioned characters are of upper-class stature, lower class people can also be classified as pomp-holes.
"Hey man, those kids on that MTV show are real pomp-holes!"