Living with his aunt as an orphan, Chuuta Kokonose has always had a constant voice in his head, but is otherwise an ordinary boy. One day, his life takes an unexpected twist when he brings home a peculiar object that transports him to a police headquarters in space, filled with creatures beyond his imagination. The Chief of the Solar System Department, Rein Brickke, reveals that the computer has identified Chuuta as a candidate for the police force. Although Misuzu Sonokata, Chuuta's schoolmate who works under Rein Brickke, has a divine appearance, she is skeptical of the inexperienced boy's capabilities. Despite Misuzu's doubts, Chuuta is determined to take the proficiency exam and prove her wrong, encouraged by the voice in his head.