Terra, the planet which belonged to humankind, had been recklessly harmed, leading to its eventual destruction in the future. Consequently, humans were compelled to evacuate and explore other worlds to sustain life and safeguard their territory. The responsibility of childbirth now rests on an advanced computer system that governs humanity. However, the appearance of the telepathic "Mu" race has caused the system to be anxious. The Mu community, who wishes to return to their native planet, Terra, has gone into hiding.
