Black Blood Brothers (ブラック・ブラッド・ブラザーズ, Burakku Buraddo Burazāzu?) is a light novel series written by Kōhei Azano and illustrated by Yuuya Kusaka. In 2006, Studio Live and Group TAC produced an anime based on the series. It is directed by Hiroaki Yoshikawa. It has been licensed for North American release by FUNimation, with the first DVD being released in February 2008.

Source: Wikipedia