Year-0133 Universal Age. Ten years have passed since it was conquered by the armed resistance of the aristocratic faction-avant-garde. Tobia Aronnaks is a student on board the SMASHION TO JUPITER spacecraft, but during an unexpected attack of a group of cosmic pirates, calling themselves Crossbone Vanguard, it discovers that between Smashion and Jupiter themselves actually had hidden agendas. After he was saved by a member of the pirates named Kincaid Nau, he was taken aboard the Mother Vanguard pirate ship, and his captain, Bera Ron, convinced him to join them. The true identity of the Pirate Group was disclosed as a partisan group, which resists the secret fraction within Jupiter, Jupiter's Empire, which intends to conquer the land.