Hero (Maoyu)

The Hero is the main lead protagonist and the greatest warrior of the Human realm who gives up on his task of slaying the Demon King after he is convinced to join her effort to ensure a truly peaceful solution to the war between Humans and Demons., he conceals his true identity and adopts the name of White Swordsman(Which of course failed) while living in a small village with The Crimson Scholar. While traveling through the Demon Realm as a peacekeeper, he dons an imposing black armor belonging to a former Demon Lord, addressing himself as a servant of the Demon King called the Black Knight