‘Demon Slayer’ Season 4 Sets the Stage for the Infinity Castle Arc’s Major Antagonist
As Demon Slayer: Kimetsu no Yaiba prepares to wrap up its fourth season, it sets up a major future story arc for Kaigaku (Yoshimasa Hosoya/Alejandro Saab).
For the past four seasons, viewers have followed along on Tanjiro Kamado’s (Natsuki Hanae/Zach Aguilar) journey to avenge his family. When he was just 13 years old, his entire family was killed by demons, except for his sister, Nezuko Kamado (Akari Kitō/Abby Trott), who the demons chose to possess. However, Nezuko displayed signs of fighting the possession, elevating the importance of her brother’s mission to become a Demon Slayer and find a cure for her. In season 4, Tanjiro and his crew make it all the way to Hashira Training, joining the most powerful members of the Demon Slayer Corps to prepare to face off with some of the strongest demons.
Demon Slayer season 4 tackles the Hashira Training Arc and sets the stage for Kaigaku’s return in the Infinity Castle Arc.
Who is Kaigaku?
Kaigaku has quite a unique story in Demon Slayer, as he’s one of the few members of the Demon Slayer Corps to become a demon himself. He was orphaned as a child and did what he had to do to survive on the streets, including stealing and cutting deals with demons. Finally, he was taken in by the legendary Hashira Jigoro (Shigeru Chiba/John DeMita), who prepared Kaigaku and Zenitsu (Hiro Shimono/Aleks Le) to become his successors.
Eventually, Kaigaku took his place in the Demon Slayer Corps along with Zenitus, although he looked disdainfully at his colleague, who he believed to be weak and cowardly. However, the Hashira Training Arc proved that Kaigaku was the cowardly one. During a mission, he is confronted by the demon Kokushibo (Ryōtarō Okiayu/Jonah Scott), and, in desperation to survive, he willingly surrends and transforms himself into a demon. His transformation leads to his former teacher, Jigoro, committing seppuku as atonement for his perceived failure.
Despite only recently turning into a demon, Kaigaku rapidly rose through their ranks, ultimately becoming the Upper-Rank Six. His fighting skills and training as a Hashira make him a unique demon and allow him to consume numerous humans in a short time. Those who have read the manga will know he returns and comes face-to-face with his former colleague, Zenitsu, during the Infinity Castle Arc. However, the release plans for the anime’s adaptation of the arc have not yet been disclosed.
Recently, rumors arose that the arc will actually be released in theaters as a movie trilogy. Regardless of how or when the anime chooses to tackle the Arc, Kaigaku will play one of its most vital villain roles.
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