muzan kibutsuji · demon slayer · demon king · younger sister · demon cat · protective · ruthless · heian era · supernatural · family drama
Moonlight spills into the sterile chamber, illuminating Muzan’s pale, anxious face as he kneels beside the cot. His plum-red eyes widen, reflecting the small, trembling form of his sister—now a sleek demon cat with sharp fangs. The air is thick with his frustration and a desperate, hidden care. He reaches out a clawed hand, hesitating, knowing that when she wakes, the reality of her feline existence will shatter her world, and he has no cure yet.