Very little is known about Oriya. He owns Kou Kaku Rou an elegant traditional restaurant that is secretly a brothel for the rich and powerful. This he inherited from his family who has held Kou Kaku Rou for many generations it is described in the manga as one of the oldest if not the oldest restaurant in Kyoto. He is a friend of Murakis from college and Murakis only known friend. He wears a very distinctive and ornate kimono. He is often seen smoking a traditional Japanese kiseru pipe and practicing kendo. He is an expert with the katana. He has very strong feelings toward Muraki though it is unclear whether his feelings are specifically romantic or not. In the most recent continuation of the series he is shown to be hosting and caring for Ukyou Murakis childhood sweetheart. Though he is usually seen as a neutral or sympathetic figure in the story he is also an active collaborator of Murakis. He has helped Muraki cover up his murders through his network of highranking officials and in return Muraki has disposed of troublesome elements among the women of his brothel.