Akaza (猗あ窩か座ざ Akaza?) is a major supporting antagonist of Demon Slayer: Kimetsu no Yaiba. He is a demon affiliated with the Twelve Kizuki, holding the position of Upper Rank Three (上じょう弦げんの参さん Jōgen no San?).[3] Over a century ago, Akaza was a human by the name of Hakuji (狛はく治じ Hakuji?)[4], a prodigious martial artist who trained under Keizo[5] while nursing his daughter, Koyuki,[6] who would later become Akaza's fiancée.