Chuuta Kokonose is an orphan living with his aunt. As far back as he can recall, he has heard a voice inside his head, but otherwise, he is just an ordinary boy—until the day a peculiar entity follows him home and transports him to a location teeming with other fantastical beings. This turns out to be a space police station, where Rein Brickke, the Chief of the Solar System Department, informs him that a computer has selected him as a potential recruit for the police force. Misuzu Sonokata, a classmate of Chuuta's who possesses an angelic appearance but a bad temper and serves as one of Rein Brickke's subordinates, doubts his suitability for the role. Initially shocked, Chuuta decides to take the aptitude test after being prompted by the voice in his head, aiming to prove Misuzu wrong.