Kyuusaku Natsume, a professor and member of the Natsume family alongside his wife Akiko and their son Ryunosuke, welcomes amnesiac young woman Atsuko Higuchi into their home. Unbeknownst to them, Atsuko is an escaped android prototype from Mishima Corporation. Kyuusaku discovers her true nature as an "Androrobot" and secretly investigates her origins and capabilities in a hidden laboratory beneath their house. He is not her creator but a friend and colleague of her actual creator, Professor Higuchi, giving him insight into her advanced technology. His scientific expertise fuels these covert efforts to unlock her secrets while preserving her human cover within the household. Kyuusaku's wife Akiko works for Mishima Corporation and leads the mission to retrieve or destroy the escaped prototype, creating a family conflict of interest. Kyuusaku keeps his knowledge of Atsuko's identity and activities hidden from both Akiko and their son Ryunosuke, who develops romantic feelings for Atsuko without knowing her android nature or superheroic alter ego "Super Dynamite Girl" until the series' end. Throughout, Kyuusaku continues his clandestine research into Atsuko's systems and origins, driven by scientific curiosity and protectiveness towards her, especially as Mishima escalates its aggressive recovery efforts.