One day, the family receives an order from their homeland to "obtain data related to the development of a new artificial organ," which a certain company is secretly promoting. In order to get close to Uesugi Shinya, a researcher who is a key figure in the development, Minami successfully infiltrates the Uesugi family as a tutor for Shinya's daughter, Haruka (Marika Ito). She also gains the trust of Haruka, whose rebellion against Shinya, who is devoted to his research, leads to delinquent behavior. However, the "normal" heart-to-heart communication with Haruka causes a change in Minami's mind, who has been trained to carry out her duties as a cold-hearted spy.