It has been seven years since Yuuichi Aizawa last visited his aunt Akiko, and now that his parents have left for Africa to chase their careers, he finally returns to the small northern town. The idea of settling here does not bring him much joy, for all his memories of the place and its inhabitants have inexplicably disappeared. Even his once‑adorable cousin Nayuki feels like a stranger, despite their childhood games together.
On the day he moves into his new house, Yuuichi begins unpacking and discovers a red headband that no one recognizes. The find becomes the first hint that prompts him to wander through the snow‑blanketed streets, piecing together fragments of his past, broken vows and hidden truths. He soon realizes that something supernatural is at work, and every new woman he meets appears connected to the memories he has lost.