Noa Eikawa, a diligent new office worker recently engaged to her boyfriend, grew up in a single-parent household with her mother. This month, she moves in with her mother's new husband, a middle-aged man. Having met him before and always seeing him alongside her mother, Noa feels at ease starting this new chapter. However, as time passes, she begins to sense unsettling gazes from her stepfather whenever her mother is away...