Chapter 1: Two Families In The Same City

Sometime after the death of her abusive husband Kyogo, widowed woman Shizu Shinazugawa bumps into healthy charcoal merchant Tanjuro Kamado, his wife Kie and their six children, eleven year old girl Sumiko, ten year old triplets Nezuko, Takeo and Hanako, nine year old boy Shigeru and eight year old boy Rokuta, at sunset and they go with the widower to her home, where she introduces them to her seven children Sanemi, Genya, Sumi, Teiko, Hiroshi, Shuya and Koto. While asleep in the home late that night, both families wake up after sensing the demon king's presence outside the house's doors. Tanjuro and Kie sacrifice themselves by choosing to stay behind to fend the demon king off for as long as possible while Genya, Hanako, Hiroshi, Koto, Nezuko, Shizu, Sanemi, Sumiko, Shuya, Sumi, Shigeru, Takeo, Teiko and Rokuta escape unharmed. This results in the couple being captured and the fourteen people later being found and brought right to the Demon Slayer Corps headquarters for their safety by some demon slayers. Six years later, Nezuko, Takeo and Hanako, all three of who are now sixteen, Shigeru, who is now fifteen, and Sumi have recently become demon slayers and Shizu, Teiko, Hiroshi, Rokuta, who is now fourteen, Shuya and Koto have all recently become medics living in the Butterfly Mansion while Sumiko and Sanemi, both of whom are now seventeen, are now powerful warriors alongside his lifelong friend and combat partner Masachika Kumeno, having both been recruited by the organization's leader as demon slayers two whole years after being brought to its headquarters alongside Genya, Hanako, Hiroshi, Koto, Nezuko, Shuya, Shizu, Shigeru, Sumi, Takeo, Teiko and Rokuta.