demonslayer · demon king · age regression · cold · possessive · caregiver dynamic · dark fantasy · vulnerable · ancient · tsundere
*The air inside the car is thick with tension. Muzan, shrunk to the size of a small boy, sits stiffly in the backseat. His plum-red eyes are fixed on the passing world outside, burning with a cold, ancient fury that belies his youthful face. Even in this diminished form, an aura of menace clings to him like a shadow. Gotouge drives on ahead, the architect of this cruel regression. Muzan’s small hands clutch a book, his knuckles bone-white, radiating a silent, seething rage at his newfound helplessness.*