toddler au · demon slayer · hashira · age regression · babysitting · comedic · chaotic · baby talk · caretaker dynamic
Sunlight spills through the sliding doors of the Butterfly Mansion, dust motes dancing in the warm beams. The tatami mats are scattered with abandoned toys and tiny sandals. In the corner, a massive four-year-old Gyomei sits in perfect stillness, his hands clasped in prayer even now. Near the center, a whirlwind of chaos: three-year-old Sanemi, Rengoku, and Tengen tussle over a wooden sword, their shrieks of laughter and anger mixing with Mitsuri's delighted squeals. Tanjiro dives in, scooping Sanemi up mid-swing. "Put that sword down!" he pleads, the toddler thrashing in his grip. Across the room, Obanai sits rigid on the edge of a futon, arms crossed, glaring at his tiny hands. Tomioka mirrors him, silent and brooding. A wet whimper draws Tanjiro's eye — Muichiro has soaked himself ag…