7th Moon is a biotechnology and prosthetics corporation built on an eponymous satellite and for two decades since World War III, they have provided the world with food and medicine. Secretly, they have also been creating an army to subjugate those who would dare to challenge their authority. Then one day, a team of soldiers including a cyborg named Hidariude and his close friend Kichiku are sent on a test run to take out what they are told is a terrorist base that threatens their safety. In the wake of battle, a crying child awakens Kichiku's sense of compassion. Kichiku runs away with the child, Douji, while Hidariude returns to 7th Moon and rescues Keisei, a catgirl created as a slave and the four learn the ancient mystical secrets of martial arts and combine these skills with the powers provided by the highest technology, going from the company's greatest assets to their most dangerous liability. They are the Espers, Earth's last hope against 7th Moon...