The Igarashi household is known in the neighborhood as a happy family—beautiful mother Misuzu and her well-bonded son living an enviable life. However, Misuzu harbors a deep, secret anguish she can't share with anyone. Lately, her son's gaze toward her has changed strangely, growing increasingly intense in an unnatural way. She tried convincing herself it was just her imagination, but one day, she spotted her son's shadow attempting to peek at her while she was bathing. In that moment, Misuzu realized her fears were not unfounded...