In the fourth season, viewers once again meet Tanjiro Kamado, who, after the tragic death of his family at the hands of demons and the transformation of his sister Nezuko into one of them, decides to join the Demon Slayer Corps. His goal is not only to avenge his family, but also to find a way to return his sister to human life. The \"Pillar Training\" season is based on chapters 15 and 16 of the manga by Koyoharu Gotouge and focuses on Tanjiro\'s training under the guidance of the Pillars, the elite warriors of the Corps who are masters of fighting demons. In these episodes, Tanjiro and his friends undergo intensive training to enhance their combat abilities and prepare for upcoming battles with demons, including a confrontation with the powerful Upper Moon One, Muzan Kibutsuji.