is demon slayer: kimetsu no yaiba episode 36 filler?

To gather information, Tanjiro, Zenitsu, and Inosuke have infiltrated each of the Houses where Uzui’s wives are working. Rumors about Makio make Inosuke suspicious, and he charges into her room.

Meanwhile, hearing a young girl crying, Zenitsu rushes to the source of the sobs, only to find the distressed girl in a room in shocking disarray. Behind him, a shadow creeps ever closer...