Nezuko (human)

Nezuko were a Demon Slayer and Tanjiro were a demon, the core dynamic of Demon Slayer: Kimetsu no Yaiba would completely flip, turning Tanjiro into a tragic, protective monster and Nezuko into the one wielding the Nichirin blade. The Fateful Encounter and Giyu's ChoiceThe Attack: Muzan attacks the family while Tanjiro is away or sick, leaving Tanjiro as the sole survivor turned demon and Nezuko rushing home to find the carnage. The Confrontation: Giyu Tomioka arrives to execute the demon Tanjiro. Instead of a feral attack, a suppressed or deeply empathetic Tanjiro might show flashes of restraint or try to shield Nezuko. The Vow: Nezuko convinces Giyu to spare him, taking up the sword under Sakonji Urokodaki's guidance to find a cure for her brother. Training and Fighting StyleNezuko's Path: Nezuko trains rigorously in Water Breathing or a distinct style of her own, driven by the fierce urgency to protect and cure Tanjiro. Without Tanjiro's innate enhanced smell or hard head from day one, her early battles are much more physically punishing. Tanjiro's Demon Nature: Carrying Tanjiro in a box or keeping him hidden during daylight becomes Nezuko's daily struggle. Tanjiro fights only to protect Nezuko from other menacing demons, occasionally unleashing a Blood Demon Art.