Guuji Chishiki no
The Shrine Priest of Knowledge. The real villain that hass been controlling Kazane and Ryuusai. Seimei and his Spirit Summons fought him once before many years ago, but now he has returned to open the Gates of the Underworld. Rikugou was the first one to realize he was back because he heard Kazane talking to him through a second head protruding from her crow, Kai. When he was mortally injured, he transfered his soul into Ryuusai's body to continue his plans. He trained Kazane & lied about what happen to her parents so she would help him open the gates of the underworld. He later also controls Touda since his blood was needed to break the final seal. He was finally killed, ironically by Kazane's necklace.