Hei, he was so badass in the first season... Then he turned into a hobo pedo 
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He also became an alcohol addict, and beat little children ;)
The characters I like are the ones who love to kill, are ruthless, and badass.
Genkaku Azuma from Deadman Wonderland
Nnoitra Jiruga from Bleach
Not many more I can think of though. I hate overrated anime characters, or ones that are just plain annoying, so it's rare for me to find one that I can actually deem as my favorite.