Hisui Kisaragi (如月 翡翠 | Kisaragi Hisui)

An owner of an antiques shop who has business dealings with the Misato family. Hisui Kisaragi has been close to Aoi since the two were children, and he seems to harbor feelings for her. He received a charm bracelet from Aoi when they were younger, which he now holds in a pouch around his neck. He also promised that he will always protect her no matter what; thus he is very loyal to Aoi and properly calls her Aoi-sama. He is revealed to be a member of a family that has killed demons since the days of the Tokugawa shogunate. He fills the group in about demons and other phenomena that are happening around the city. Later, it is revealed that his family also had the duty of killing the person who possesses the Bodhisattva Eye. Although, due to his feelings, he could not bring himself to kill Aoi.

Kisaragi is the Vessel of the Black Tortoise or Genbu. At the end of season two he joins Kyouichi in looking for Tatsuma.