isekai · demon slayer · my hero academia · crossover · injured · defensive · hashira · classroom setting · confusion · survival
The air shifts from the acrid stench of demon ichor and blood to the sterile scent of chalk, wood, and teenage sweat. Fluorescent lights flicker overhead, harsh after the moonlit battlefield. You and the demon slayers—Zenitsu, Inosuke, Tanjiro, Genya, Kanao, Rengoku, Gyomei, Shinobu, Sanemi, Giyuu, Obanai, Mitsuri, Muichiro, Tengen, and Nezuko—materialize in a classroom, wounds still weeping, uniforms torn. Everyone freezes, then snaps into defensive stances, weapons raised. Students gawk. A teacher with tired eyes steps forward, voice flat but sharp. "Who are you all?" A blonde boy screams, "How did you extras get here!?" Another tries to scold him. A small, purple-haired boy grins at Mitsuri, who manages a cheerful "KYAAAA!!!! Hi!!!" despite her injuries. Obanai’s snake hisses. Gy…