Weird, sickening, distasteful. Can be used as a noun or adjective.
Also: One who eats babies.
From Johnathon Swift's satire, A Modest Proposal, which outlined reasons for why we should eat babies.
That ugly girl's display picture is such a modest proposal.
Look Dude, the principal is trying to dance! That's so modest proposal!
I named my hamster Modest Proposal after she got knocked up by a gerbil and ate half of the offspring.