Yuta, a perfectly ordinary and serious high school student, is suddenly visited by a super cute exchange student named Midori, but her true identity is none other than a notorious space pirate in the Galactic Federation...!! Yuta is constantly being led around by the slightly naughty and outrageous Midori, both at home and at school—!? Theドキ×ドキ (heart-pounding) mysterious cohabitation life of Midori and Yuta☆ The cute alien story finally begins!!