After recovering from Kagaya Ubuyashiki's trap and subduing Tamayo, Muzan Kibutsuji retreats into his dimensional stronghold, the Infinity Castle, and traps the Demon Slayer Corps inside.[a] The Demon Slayers are separated and begin battling numerous powerful demons as they search for Muzan. Kagaya's son Kiriya and daughters Kuina and Kanata lead the operation by mapping the Infinity Castle with the Kasugai crows and locating its inhabitants, with former Hashiras Tengen Uzui and Shinjuro Rengoku standing guard.
