ADOPTED Kosa is a vampire. He tries not to feed on the blood of others, and instead drinks from himself. However, if he sees anyone bleeding, he can't control him self and becomes a whole new person, who is a lot more insane and blood thirsty than he is.
"Yes my reasons for killing your brother were not the best motives." He pauses raising his hands to his face. " but I like the feel of blood on my hands" he smiled and then frowned. "I'm going to hell"