Ok so this is actually a tough question for me because even though I definitely have characters I don't like, I don't actually hate any of them. For example, I dislike Serizawa because of a specific part of the fandom, but apart from that, I actually really like him and his character (mostly because I can relate to him ahem) but if I had to pick a character I dislike the most it would have to be Minori. Don't get me wrong, I would love to see a mp100 future story where she has changed her ways and even grown to be great friends with Mob but considering the story as is, she's just the cliché rich girl bully who needs to be knocked down a peg and forced into therapy. Again though I don't hate her. I think she's pretty and I've fallen in love with bully characters before who have shown they can be redeemed but she is definitely the one I dislike the most.