One day, Tsukishima Minori woke up in an unfamiliar small white room. Beside her, Ichi- a boy who possess a rabbit’s ears, tells her that he is her guardian spirit. He also told her the room they are in is called “Kuranoa” – where it shows/represents a person’s heart. At the same time, he tells her that she lost her memories during the accident while she was on her way to school and same thing happened to her twin, Shiori. To her surprise, she and Shiori now shares the same body.