The series begins with Mao Onigwara attempting to leap over a three-tier vaulting horse in her gym class. She doesn't make it. After talking with a sympathetic Misora, her toy tank Mi-Kun arrives to pick Mao up due to a giant cute alien about to land in Yokohama, Kanagawa Prefecture. There is a slight argument about the Prime Minister of Japan spending more budget for the United Defense Force, but Rikushiro Onigawara quickly ends the complaining by stating that the only way to defend against cuteness is with cuteness. The giant alien arrives and reveals itself to be a large, cute cat wearing a parachute. Mao, who had been waiting for its arrival, attempts to bonk the alien with her baton, but a gust of wind carries the cat away, causing Mao to scrape her knee. Mao is helpless to do anything because the cat is in the skies, an area where the Ground Defense cannot go. Suddenly, Second-Lieutenant Misora appears on her toy plane, Hayate to lend support. However, the cat eventually lands in the water where neither Mao nor Misora can go due to the area being inaccessible.