Aoyama Masaya, from Tokyo Mew Mew. Seriously, perfection annoys me >>.

Sakura, from Naruto. She's a fangirl! Why is the female with the biggest part in the entire manga a fangirl?! It annoys the heck out of me. Not to mention she's so loud, violent, and obnoxious. And whiny - the girl can't go three seconds without complaining about something.

Kikyo, from Inuyasha. I can't stand this girl. She can't let go of her past, and she can't let anyone else let go of it either, namely Inuyasha. She's two-faced, and she can't seem to decide whether she's on the good side or the bad side. So, instead of doing the smart thing and picking, she flip-flops between the two until you're hopelessly confused and want to bang her head against something hard and scream at her to just CHOOSE ALREADY! *breaths heavily*

I think that's the big ones, although there are a few other characters I also don't like very much. >>

Sakura from Card Captor Sakura.

Sure, she's cute, but if anyone honestly denies she's a mary-sue, you need to look harder.

"I'm Sakura Kinomoto, I'm good at sports, and a little bit clumsy, and I hate math and ghosts"

No real flaws, and everyone adores her.

"OMG SAKURA IS SOOOO CUTE GAIS"

If she had even one flaw, I wouldn't think this way of her.

Even in Tsubasa, she's no better.

Can't think of one right now, but yeah annoying characters
are.... annoying. xD

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Paste siggie here. ^^

Kikyo for obvious reasons
and Suzumiya Haruhi for being such an egoist

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marimo-lover.deviantart.com ~~

The last annoying character I've read is Yuki from Vampire Knight. D=
Characters like that annoy me the most. DX
Sakura from Tsubasa Reservoir Chronicle. I feel sorry for the poor Syaoran. =___=; Probably because of her I put the manga on hold.
Hiyo from Love Monster, I don't even need to explain why...

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"Beware How You Take Hope From Another Man."

well,almost every character in Naruto is annoying,

but recently i hate an annoying evil/antagonist character that always smiling with his/her eyes closed.....with evil motive

well,recently i just hate prince canute from Vinland Saga...
and a samurai lookalike character from kurohime....

and,oh yeah i didn't like a character that just get in the way of main character....pretty annoying....

I'd have to say :

-Tohru from Fruits Basket : Man...all the optimism seriously annoyed the heck out of me.
-Tenma from School Rumble : Can you make a more useless character?? Why does Kenji like her anyway?
-Kikiyo from Inu Yasha : How many times can a person die and be brought back to life? She just...won't...die! At least till later chapters...or so I heard since I stopped reading it.
-Those two main girls from Fushigi Yugi : I dropped the whole thing when I heard her (Miaka, was it?? I hate her so much, I've forgotten her name) whine for "Tamahome" again...and again...and yet again..
-Shampoo, Mousse, Kuno and Kodachi from Ranma 1/2 : God....why do they exist
-Onigiri from Air Gear : What purpose 'exactly' does he serve in Kogarasumaru? He's a serious waste of character!
-Kon from Bleach : Made me bang my head against a wall every single time 'cuz I couldn't inflict harm on my PC.

Edit this when I remember more...

Oh, almost forgot!
-Them annoying weak, innocent, helpless streotypical shoujo manga heroines. In real life, nobody's gonna come save you so just zip it!! Or get a brain!!!

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'When people talk to God, it's called prayer. When God talks back, it's called schizophrenia.'

Sakura from Naruto (but it's better in shippuuden)
Usopp from One Piece (he is a nuisance)
Reborn from Hitman Reborn (he talks too much)
Izumi Ako from Negima (pathetic...)