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). Over a century ago, Akaza was a human by the name of Hakuji (狛はく治じ Hakuji), a prodigious martial artist who trained under Keizo, a martial arts instructor who took him in as a student, while nursing his daughter, Koyuki, who would later become Akaza's fiancée.