FFIV: I don't know ? Maybe Tellah ? But it's because we don't see him for a long period.
FFIV The After Years: Leonora. I hate how she becomes fond of Palom even if he's still an ass with her.
FFV: Krile but I really like her too LOL
FFVI: Umaro, because his backstory is not really explained.
FFVII: I absolutely can't stand Caith Sith, I find him so annoying everytime andf I'm glad we don't have to bring him often.
FFVII Crisis Core: Genesis. He's not bad but he could have been better.
FFVIII: Seifer. Another character I can't stand. I never managed to connect with him.
FFIX: Quina, but I still like them. It's just the one I find the less instesting.
FFX: Kimahri. I still like him though.
FFX-2: Paine. I never connect with her personality.
FFXII: Basch but he's great too :P
FFXIII: Snow. He's a good guy but all the "hero" thing annoys me.
FFXIII-2: Alyssa. I saw her betrayal coming so early ? I've always known she was an enemy :P
FFXIII Lightning Returns: I don't really know ? Most of the characters are recurring ones so.
FFXV: Loqi ? He's just a faithful soldier to the Empire and it makes him a bit annoying :P