Well, this may not count entirely, but I'm gonna put it here, anyway.
I can't watch King of the Hill.
Not because it's bad. Hell, the show is genius at times. One of the best episodes I did see was Hank and several other characters parodying 12 Angry Men with a lawnmower. It was so funny. Partly because Hank and co don't realize they are being funny.
So, why can't I watch this show? Peggy.
I HATE Peggy. She's annoying, idiotic (but thinks she's smart), arrogant, annoying, lacks any degree of common sense, and causes plenty of problems. Did I mention she's annoying? I hate this one character so much, for fear of an episode being Peggy centered, I can't ever watch it. Which is unfortunate.
And I get the joke. It's just not funny. She's too annoying to be funny.
I remember watching an episode where she effectively ends up smuggling drugs into jail without knowing it. All because she's too full of herself to realize that no kid would write to a substitute teacher. In the end, she almost gets in trouble because the convict can basically just tell the warden about the smuggling. But, because the crook was too dumb to not take his drugs/evidence, and Hank pointed out that it was his word against hers, she was let go. Does Peggy have any humility? Nope. She walks out telling Hank she told him she could take care of it.
I really hate that character...