19. The McPoyles - It's Always Sunny in Philadelphia
The McPoyles are pretty much the comedy version of that crazy family from Texas Chainsaw Massacre. They're weird, incestuous, and spend altogether too much time sitting around in bathrobes drinking milk. Human adults are not even really supposed to drink milk, but that's the least of that family's problems. They are the mortal enemies of the Paddy's gang, and both groups exist in the same heightened reality where it's totally OK for each of them to basically take turns committing atrocities against one another. Are the McPoyles the only ones at fault? No, of course not. But there's something so indescribably creepy and unsettling about them that just catching a glimpse of one of them (or, god forbid, the entire family) is enough to make your skin crawl.