It will happen in the not-too-distant future. Nuku-Nuku appeared one day and moved in with the Natsume household. Nuku-Nuku assumed the identity of a lovely girl named Atsuko Higuchi after losing her memory. Ryunosuke, 14, was all smiles because she was so lovely and caring, and she was also a fantastic cook. However, shortly after her arrival in town, a series of inexplicable events began to occur in Maneki City, including experimental machinery going berserk, screaming fighter aircraft flying low, and mass destruction throughout the city. In every case, a strange girl was seen near the crime scene.