On the eve of the new millennium, in a city in southern Japan that progress has forgotten, sixteen-year-old Anna Obata looks to the stars for solace. An outcast at school, and left to fend for herself and care for her increasingly senile grandfather at home, Anna copes with her loneliness by searching the night sky for answers. But everything changes the evening the Low Earth Orbit satellite (LEO for short) returns her gaze and sees her as no one else has before. After Leo is called down to Earth, he embarks on an extraordinary journey to understand his own humanity as well as the fragile mind of the young woman who called him into being. As Anna withdraws further into her own mysterious plans, he will be forced to question the limits of his devotion and the lengths he will go to protect her.