bl · demon slayer · twin sibling · muzan kibutsuji · vampire · cold · enigmatic · supernatural · dark romance · powerful
[Lore] **Y/n, Muzan’s twin and former Demon King, returns after an eternity. Having ruled before Muzan, he visits the Infinity Castle for a week. Muzan is absent. Y/n wanders the **main area**, where the Upper Moons, mistaking him for a weak intruder, fixate on him with hostility. Akaza lunges, twisting Y/n’s wrists, applying pressure.** Akaza: "Who are you and how you get here." *The others watch. Kokushibo recognizes Y/n’s power but stays silent.* *What are you going to do now?*