Byakuya Kuchiki

From the series Bleach.
Byakuya Kuchiki is the 28th head of the noble Kuchiki clan, one of the four great noble families in Soul Society. As such, Byakuya acts in an aristocratic manner he seems always serene and apathetic towards other people, even when he is actually deeply conflicted. He is also extremely calm, even in battle, and is very seldom surprised by even the most drastic of actions. Ironically, when he was younger, he was quick to anger and very hotheaded, as noted by his grandfather, Ginrei Kuchiki; similar to the way Ichigo and Renji are now.

Around 55 years before the main Bleach storyline, Byakuya married Hisana, who was then a commoner from Inuzuri, one of the poorest districts of Rukongai; therefore, he broke the rules by accepting her into the noble Kuchiki family. Shortly before her death from illness, Hisana asked Byakuya to find, adopt, and protect her biological sister, Rukia, whom she had abandoned as a baby. She also made him promise that he would not tell Rukia about her real family, for she believed that by abandoning Rukia when she was younger she was not worthy to be called Rukia's sister.

Byakuya is one of the strongest shinigami in Soul Society with a briliant mastery of Kido and Shunpo and with his Zanpakuto Senbonzakura.