Which manga chapter of Natsume Yuujinchou has a mask youkai that possesses people?


Which chapter was the chapter where Natsume pretends to be Matoba's blind
shiki so that he can feel people's faces and determine whether they are being
possessed by a youkai? From my memory, the youkai was a mask that attached
itself to people or something...




Manga chapter 53-54. Anime season 5 (Natsume Yuujinchou Go) episode 4.

