Yami to Hikari no Sanctuary

Souji is the successor of the Izumo family’s traditional martial art form to defeat vengeful beings that harm humans. He accompanied his osananajimi Arisu, the daughter of the head of a world-leading zaibatsu, as her bodyguard to the distant island of Niizajima. She transferred to Kamikura Private Academy to look for her older sister, who had disappeared without a trace.

There were many strange ‘rules’ on the island, which they believed were set in place to cover up a ‘secret’. With the help of Arisu’s osananajimi Yuuri, zaibatsu rival Claudette and mysterious classmate Julie, as well as some strategy, they gradually got closer to the truth of the island. But what awaited them wasn’t Arisu’s older sister, but countless ‘apparitions’ that had been talked about in many stories.