Kaigaku, Kimetsu no Yaiba Wiki

Kaigaku (獪 (かい) 岳 (がく) , Kaigaku?) is a supporting antagonist in the Infinity Castle Arc of Demon Slayer: Kimetsu no Yaiba. He is a demon affiliated with the Twelve Kizuki, holding the position of Upper Rank Six (上 (じょう) 弦 (げん) の陸 (ろく) , Jōgen no Roku?), replacing Daki and Gyutaro after their deaths. Kaigaku was a former Demon Slayer and Zenitsu Agatsuma's senior disciple under the former Thunder Hashira (鳴 (なり) 柱 (ばしら) , Nari Bashira?), Jigoro Kuwajima. However, sometime during Hashira Training

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