Son Gohan (DragonBall Z)
Although he's a crybaby at first, Gohan actually does become a great, courageous character in the later parts of DragonBall Z. Even though he doesn't like to fight, he still agrees fights for the fate of the world when battling Cell in the Android arc. By the last arc in DragonBall Z, he has become more of a humorous character and seemingly gains the childhood he never had as a kid. From start to finish, I love the character development of Gohan throughout DragonBall Z.
Without a doubt, Gohan is my favorite manga/anime character of all time. A very admirable character to me in the DragonBall series and very likable to me as well.
Link (The Legend of Zelda)
What he lacks in speech, he makes up for in his skill and puzzle-solving abilities. Since playing the Ocarina of Time back in 2003, I've loved Link as a character. In whatever iteration he's in, whether it be realistic, cartoony, or a little of both, Link is still that same, silent hero that I've come to know.
Definitely my favorite video game character of all time.
Dr. Kenzō Tenma (Monster)
Interesting character. At the beginning of this manga/anime, he is a neurosurgeon at the Eisler Memorial Hospital in Düsseldorf, Germany. he is the Head of Neurosurgery who is well-liked by the department's director. In the first episode of Monster (I've never read the manga before), he is about to prepare surgery on a young boy who is suffering with a bullet wound. The Chief of Surgery and the department's director call Tenma to work on the Mayor of Düsseldorf, who collapsed in his holiday home. Tenma tells the director to get another doctor, called Dr. Boyer, to work on the mayor instead and says that he is the only doctor at the hospital qualified to work on the young boy. The director refuses to listen to him and again orders him to work on the mayor. Tenma's conscience gets the best of him and he decides to work on the young boy instead. Tenma saves the young boy's life, while the mayor ends up dying.
I won't go further than that into the story, but I will say this. Nine years after that surgery happens, the young boy, now about 21 years old, turns out to be the "Monster" in which the manga/anime series title refers to. He's not actually a monster, but he ends up murdering a lot of people throughout the series. His goal is to be the last person left in the world. Tenma figures this out through a series of many events, and decides to leave his job and try to go end the life of the "monster" he feels he created due to saving his life nine years ago.
Anyway, this Dr. Tenma is a very cool character. He knows how to react in many situations, and even in the most dire situations he remains calm and tries to think of the best way to solve a situation. He also helps heal people with his neurosurgeon skills who end up getting hurt in the series.
If you are 16 or older and can handle the dark atmosphere this series has most of the time, I recommend you watch this. This series can be violent, but it doesn't get to be absurdly violent (I personally hate overly gruesome violence; that's why I dislike 99% of all horror movies). It can be hard to follow sometimes, but this was one awesome, thrilling series to watch. If you've never heard of it, it was made by Naoki Urasawa, who is the same guy who did Pluto. Great manga artist.
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I have many other favorite characters, but I think I'll leave it at that. Atom is my favorite character from Astro Boy as well. I think Ghost pretty much summed up my feelings about him.
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But hes a favorite of mine too... 
Astro Boy|鉄腕アトム [sigpic][/sigpic]
But here it is acceptable. It's been a while since I read the books, but Charles Wallace is powerful but humble and self-sacrificing. A cool character all around.
