Hmm..... Most hated fictional characters..... Well there's.....
Ellen Faustino from The Supernaturalist,
Orpheus from Inkspell and Inkdeath,
Jon Spiro from Artemis Fowl: The Eternity Code,
Morgana and The Clockwork King from The Grey Griffins series,
Jeb Batchelder (or however you spell his name) from Maximum Ride,
and President Snow and President Coin from The Hunger Games series.
Yep, I think that's everyone I hate. Or don't like with a passion and wouldn't mind throwing off a bridge. Yeah, that's pretty much it. There are probably more, but I can't think of them right now.