As a legendary hero nears victory against a necromancer known as The Corpse God, things take an unexpected turn with the dark sorcerer’s final gambit—reincarnation magic. This last-ditch effort catches the brave fighter off guard, and now he’s a boy named Polka Shinoyama in a whole new world! The showdown between good and evil just got epic.

Just as the planet approached its third World War, individuals with superpowers appeared from around the globe to maintain peace. They became the symbols of their respective nations, striving to limit crime and bring evildoers to justice. Teenage heroine Teru "Shy" Momijiyama is Japan's representative in the world of heroes. When a mysterious threat called Amalareiks emerges, Shy must work together with her fellow heroes to stop them at all costs.

Osamu and Youko Sonoyama want more than anything to adopt every child from Soramame House, but the wealthy couple can only pick one due to their increasingly old age. While they contemplate this delicate decision, one child's alluring beauty and gentle soul instantly draw them in. Two months later, the Sonoyamas welcome 13-year-old Hitori into their warm and loving home. However, Hitori's humble and overly polite exterior is merely a masquerade. In reality, Hitori is a carefully crafted character played by identical twins Migi and Dali. For them, being the ideal child of this kind couple is merely a stepping stone to infiltrating a certain quiet town. While dutifully protecting their cover, the twins work toward their true objective: to discover the truth behind a past incident that left them with a burning desire for vengeance.