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The Heavenly Demon and his nemesis, the Ice Witch, die in their final battle and are reborn as ordinary human twin siblings. As they reach their teenage years, the world becomes unstable due to organizations formed by other reincarnators. The twins try to conceal their past-life abilities, but people connected to their previous lives begin to gather around them, including the Ice Witch, who now stands beside the Heavenly Demon as an ally. Despite wanting a normal life, they are pulled back into chaos, raising the question of whether the Heavenly Demon will once again become the strongest in the world.