Kazuhiro Mitogawa

A boy who used to belong to the Agency. He was enthralled by the sesshōseki, hoping to use the Kyuubi's powers to revive his mother, an exorcist who had been previously killed in action. When Lady Tamamo appeared to him in the Vatican's library, he willingly became one of her minions, sparking off the events in Ga-Rei: Zero and the first 7 volumes of the manga. He was the one who gave Yomi her sesshōseki, and later took it away after he was displeased with Yomi giving one to Kensuke. He mentions a "Lord Tamamo" as his overlord, the former mistress of the Kyuubi before its sealing. After Yomi's demise, he is next seen participating in the Jugondō coup as Setsuna's underling. He removes Kagura and Kensuke's souls from their bodies, and takes them to a spirit dimension he calls "Tamamo Garden", where they encounter Lady Tamamo.

He uses insect-related magic, and seems to have powers related to the sesshōseki, such as being able to remove the souls of people who possess them. One of his eyes contains a sesshōseki. He was later killed by his resurrected mother, before Izuna could avenge Yomi. He wanted to expose the world they live in to the public, in a way he succeeded since the kyuubi was seen around the world.

(source:Wikipedia)