Nano Shinonome is a humanoid android created by the young genius Professor Shinonome, known as Hakase. She lives with Hakase and their talking cat Sakamoto in the Shinonome Lab, acting as the homemaker and caretaker. Nano appears to be a teenage girl and is one of the main protagonists of the story. Her background is defined by her creation as a robot; she has a prominent metal key protruding from her back that she cannot remove, and she is constantly subjected to unsolicited upgrades from Hakase, which serve as a recurring source of humor and anxiety. In terms of personality, Nano is reserved, shy, and earnest. She possesses a gentle and maternal nature, especially toward Hakase and Sakamoto, but she is also deeply insecure about her robotic identity. Her primary motivation is to live a normal life and be accepted by others as a human girl. She fears that her mechanical traits will betray her, and she often panics at the prospect of being discovered, frequently exclaiming that she does not want to be found out. Despite these worries, she is kindhearted, sincere, and tries her best to fit in at school with her friends. Her role in the story centers on navigating everyday life while concealing her true nature, providing a contrast between the absurd and the ordinary. Key relationships include her bond with Hakase, who treats her both as a beloved creation and a friend, leading to a mix of affection and frustration. She also shares a close companionship with Sakamoto and forms genuine friendships with Yuuko Aioi, Mio Naganohara, and Mai Minakami, through whom she learns about social norms and emotional expression. Over the course of the series, Nano undergoes subtle development, gradually moving from self-doubt toward greater self-acceptance, though her desire for normalcy remains a core struggle. Notable abilities include superhuman strength, agility, and durability, as well as a range of upgrades that grant her unique functions such as high-speed movement. She often restrains these abilities to avoid attracting attention, but they occasionally come into play in comedic or emergency situations.