Doma is a cold and calculating individual with an extremely keen intellect. His high intelligence may be the reason why he looks down on humans and human demon slayers, genuinely believing that they are pathetic and stupid. But if it’s a demon, he adores them and is very enthusiastic and cheerful around them. His Master, Muzan formed an organization called the Twelve Kizuki, to kill the human Demon Slayers. His best friend was Akaza, who is dead, not to be spoken of.