He's in so much denial of his own pathetic abilities, that his only power up after 3 years of training, was a single Shadow Clone which added only a single dog head to an ability he already had as a 12 year old, and yet he still believes he will surpass Naruto someday. U_U
Karin, because to me she is the most annoying and irritating character in the series.
And.
Danzo, because he was just all around unlikable to me. Kishi did a great job with his character, because he made a villain that most people would hate and root against, which is how a true villain should be written in my opinion.
I don't particularly hate any character. But I have things that hate about some characters.
Sasuke: Arrogance
Sakura: Obsessed about Sasuke.(I understand that she loves him but her reasons for loving him are terrible.)
Karin: Almost same as Sakura.