Volume 21 (Ancient Memories) uncovers long-hidden truths about Muzan Kibutsuji and the origins of demon power. Flashbacks reveal historical connections that reshape the understanding of the conflict. Tanjiro edges closer to his ultimate confrontation with the demon king. The remaining Hashira push beyond their physical limits. The narrative blends past and present seamlessly. Emotional revelations intensify the final battles. The series’ themes of legacy and inherited willpower reach their peak. Readers gain deeper insight into Sun Breathing’s origins. The scale of destruction grows immense. This volume builds anticipation for the climactic showdown.