Kento, who had fallen down the stairs and broken his dominant hand, was left without his mother. Unable to even eat properly, he was rushed to his side by his neighbor, Kozue, whom he had known like family since childhood. Under her devoted care, Kento unknowingly became consumed by lust, fantasizing about Kozue and indulging in masturbation. However, Kozue witnessed this moment. They both realized that their hidden feelings for each other were gradually being exposed.