An orphan boy named Chuuta Kokonose lives with his aunt. He has this voice in his head as far as he can recall. One day, mysterious creatures follows him home and teleported him to a place populated with more exotic creatures. Rein Brickke, the Chief of Solar System Department at the space police station informs Chuuta that he has been selected as a potential candidate to join the police force by the computer. Misuzu Sonokata, a girl with an angelic face but ill temper, who is from Chuuta’s school and also Rein Brickke’s aide, doesn’t think he is suited for the job. In confusion, Chuuta determined to take the aptitude test to prove Misuzu wrong and also follows the voice in his head that urged him.