An isolated girl named Ria, who lost her parents and lived as a recluse, faces complete loneliness when her only friend decides to move overseas. Discovering the existence of custom-made bionic robots, she orders one modeled after the appearance of her former crush—her friend's older brother. She begins a daily life consumed by sex with the robot. However, the robot starts whispering affectionate words to her, then confesses: "Ria... actually... I'm about to be taken away..." After briefly experiencing happiness, Ria once again confronts solitude—but resolves to overcome this despair.