In "Demon Slayer: Kimetsu no Yaiba," the element of mythology and legend heavily influences the storyline, characters, and world-building. The series draws inspiration from various traditional Japanese myths, legends, and folklore, incorporating elements such as demons (Oni), supernatural abilities, and spiritual practices. These mythological elements add depth to the narrative, create a rich and immersive world, and provide a unique cultural context for the characters' motivations and actions. The use of mythology and legend also helps to explore themes of good versus evil, redemption, and the power of human spirit in the face of adversity. Overall, the infusion of mythology and legend in "Demon Slayer: Kimetsu no Yaiba" enhances the storytelling and contributes to its popularity among fans.