Summary:
Twenty years ago Pluto was destroyed by an asteroid which was later called Thanatos. After destroying Pluto, Thanatos was caught in Pluto's orbit. Many believe that the asteroid will stay in Pluto's orbit, while others believe it will make its way to Earth and destroy it. Together they formed the ISDA, the International Solarsystem Development Agency, to find a way to stop Thanatos from making its way to Earth. Jin Kamishina and his family, along with many others, were on their way to the moon when their shuttle was struck by a meteor from Thanatos, leaving Jin as the only survivor. Two years later Jin continues life as an ordinary person, that is until he witnesses a murder by a Dragon-like creature. After being cornered by the creature, Jin is knocked off a building and saved by a mysterious girl named Toa. Because of this Jin is selected by the ISDA to be a Dragonaut, humans with dragon partners. Together with Toa, Jin dives deeper into the secrets of Thanatos and the dragons.
