Because Kokoro is constantly bullied at school, she hardly ever leaves her room anymore. But one day, a portal appears in her mirror, leading her to a magical castle on a remote island. There, she meets six other teenagers who are also struggling with their own hardships. The mistress of the castle — a mysterious, masked girl known as the "Wolf Queen" — offers the group a game: whoever finds the secret room will have one wish granted — no matter what it is. As they search for the room, the students grow closer and share their emotional stories. But whose wish will be granted in the end?