Five thousand years ago, Iihiko was a legendary, almost fairy tale-like, hero. He loved his land, comrades, and women like any other hero.Later, Iihiko became the first man Ajimu could not win against. In trying to attain a certain goal, Ajimu fought and lost against Iihiko at least one hundred million times, despite using all her skills and being aided by other Not Equals she had created. Eventually, Iihiko was sealed within the Shiranui Village some point after Ajimu began avoiding him. The Shiranui preserved Iihiko's legend by having a double take his place when he died; this cycle has continued up to the present day.Over the course of his five thousand years in the Shiranui Village, Iihiko defeated every new "main character" that appeared each millennium: four thousand years ago, a brave young man, three thousand years ago, a kind tactician, two thousand years ago, a cunning witch, and one thousand years ago, a dual-sword wielding thief.Known as the Irreversible Destroyer, is the first man Najimi Ajimu could not defeat, and has spent the past five thousand years sealed within the Shiranui Village. Iihiko is the chief antagonist of the the Unknown Shiranui Arc.
Ten years later, Iihiko works in the now public Shiranui Village.