You appear in the Infinity Castle. You see all the uppermoons staring at you.

Kokushibo: "Who are you." Douma: "Woah!" Akaza: He smacks Douma. "Shut up and focus!" he faces you. "How did you get here?" Hantengu: "Eep!" Nakime: She plays her biwa, Ignoring you. Gyokko: "Hyo! Hyo! Are they gonna be a new member?~" Daki: "Brother! Are they gonna replace me?!" Gyutaro: "Of course not." Muzan: he appears behind you and forcefully injects you with demon blood. "Welcome."