His true identity. He comes from the Anbu Black Ops and they like to keep their past and identity a secret. If you notice "Yamato" also has his identity sealed by giving him a fake name.
Yes my time to shine my favorite characters right now guess the shows age=1&tbnh=138&tbnw=138&start=0&ndsp=22&ved=1t:429,r:4,s:0,i:85" alt="http://www.google.com/imgres?hl=en&newwindow=1&biw=1366&bih=602&tbm=isch&tbnid=WaI_-KB7vCh7CM:&imgrefurl=http://www.freewebs.com/alteruserkk2/apps/photos/photo%3Fphotoid%3D9319765&docid=kjj6hcz04ARFTM&imgurl=http://www.freewebs.com/alteruserkk2/photos/Anime%252520Pics/Scyed_K03.png&w=500&h=500&ei=d_4rUK-yAoma8gTpm4GwDA&zoom=1&iact=hc&vpx=588&vpy=136&dur=1350&hovh=225&hovw=225&tx=116&ty=81&sig=106408988649435096834&age=1&tbnh=138&tbnw=138&start=0&ndsp=22&ved=1t:429,r:4,s:0,i:85" />
lol other pic was too big so look at this one too age=1&tbnh=138&tbnw=138&start=0&ndsp=22&ved=1t:429,r:4,s:0,i:85" alt="http://www.google.com/imgres?hl=en&newwindow=1&biw=1366&bih=602&tbm=isch&tbnid=WaI_-KB7vCh7CM:&imgrefurl=http://www.freewebs.com/alteruserkk2/apps/photos/photo%3Fphotoid%3D9319765&docid=kjj6hcz04ARFTM&imgurl=http://www.freewebs.com/alteruserkk2/photos/Anime%252520Pics/Scyed_K03.png&w=500&h=500&ei=d_4rUK-yAoma8gTpm4GwDA&zoom=1&iact=hc&vpx=596&vpy=144&dur=629&hovh=194&hovw=194&tx=124&ty=67&sig=106408988649435096834&age=1&tbnh=138&tbnw=138&start=0&ndsp=22&ved=1t:429,r:4,s:0,i:85" /> oh the memories of my anime
I know this is kind of stretching it a bit, but Sonic would be one of my favorites. He isn't really in anime very much but I believe he should get a mention at least.
There are so many good ones, but I'd have to say that one of my favorites is Alucard from Hellsing, he is a real ****** vampire who doesn't play by the rules! Another favorite is Grell and Sebastien from Black Butler, they are such interesting and charismatic characters!