|Appearances||Forbidden Siren 2|
|Voice Actor||Tomo Uchino|
Ryuhei lived as a specialist archaeologist in Tokyo, but after the death of his wife, Yayoi, he moved to Yamijima with his son to conduct a scientific investigation. One day, the two go to the rocky area in the harbor to search for a medal dropped by Shu, and by chance Ryuhei ends up taking in an amnesiac girl. Her face bears an eerie resemblance to that of his wife when she was young, and her strange behavior makes him suspicious, but seeing his son take to the girl like a big sister Ryuhei names her Kanae and they begin living together. However, the islanders residing in the area, including Tsuneo Ohta, believe that Kanae is the cause of the strange happenings and gradually the discord intensifies until finally, just before the night of the tragedy begins - on the day of the incident in which the residents of Yamijima vanish, he is killed and turned into a Shibito by a Shiryo.