Mao Onigawara is a happy 8-year-old grade-schooler and the granddaughter of Chief of Staff of Ground Defense Force. Equipped with her cloverleaf-shaped badge which enables her to transform (but gives her no special power whatsoever), Mao and her best friends (granddaughters of Chief of Staff of Air and Marine Defense Force, respectively) will defend Japan against the invasion from "cute aliens," who are way too cute to be dealt with by regular armed forces. (Source: ANN)

Beautiful sisters Ai, Mai, Mii, their android maid Mea and slippery pet ferret Unagi make an amazing journey together through time and space without ever leaving their beloved mansion behind! Following the clues of the strange dandelion-like "Popotan," the girls are theoretically seeking the person who has the answers to their most personal questions, but they seem to have more than enough time to take side trips, meet new friends, visit hot springs and occasionally operate the X-mas shop they keep in the house along the way! Yet, the girls' ultimate destiny holds more than a few surprises of its own, and not every moment is filled with hilarity, as moving through time means having to leave friends behind as well.

The story is set in Aquafall, a fantasy world abound with water and greenery, and populated by dragons and fairies. Meteorites suddenly bring forth evil creatures that threaten all living things on the planet. The fairy Syrup assembles the Aquafall Defense Force, with three girls of the dragon clans as recruits. The story follows Syrup and the dragon girls Leviathan, Bahamut, and Jörmungandr as they work together to battle enemies and grow up.

The story takes place in a trading city Ert'Aria. Leicester Maycraft is an item engineer belonging to an adventurer guild "Oasis." One night, he is at a party with his friends to see a meteor stream on the rooftop of a chapel. One meteor grazes them and hits the steeple of the chapel. There he finds a secret room and a sleeping girl. The girl wakes up and says "You must be my father!" The encounter with the mysterious girl brings an unexpected adventure to Leicester.