Figure 17: Tsubasa & Hikaru

Tsubasa Shiina is a shy 10-year-old girl who has just moved to Hokkaido to live with her father. Struggling to connect with her classmates, she keeps to herself. One night, she sees a UFO crash in the nearby forest. Investigating, she finds the injured pilot, known as "D.D.," and a terrifying alien called a Maguar that had hatched on the ship. When the Maguar nearly kills her, an alien lifeform merges with her body, creating the powerful Riberus battle armor Figure 17, which quickly defeats the creature. The lifeform then takes the name Hikaru and transforms into Tsubasa's exact double. With Hikaru by her side, Tsubasa begins to open up to others. But their newfound bond has a greater purpose-Maguar eggs are hidden across Hokkaido, and they must use Figure 17 to destroy the creatures as they hatch, holding out until reinforcements from D.D.'s home planet arrive.