Follows Nono, a country girl who dreams of becoming a space pilot who, due to a chance encounter with an actual space pilot finds herself becoming part of the elite Fraternity. Made up of teenage pilots called Topless, and armed with quasi-humanoid weapons called Buster Machines, the Fraternity's mission is to protect the people of the Solar System from attack by swarms of space monsters.
The series revolves around Nono's quest to become like Nonoriri, her relationship with Lal'C Melk Mark, the first Topless she meets whom she immediately idolizes and the hard work she believes she has to do to be 'worthy' of Lal'C's attention.