Natsume Yuujinchou: Season 5, Episode 6

5 - 6: Soundless Valley

Natsume is chased by two yokai who cast a voice-sealing spell on him. A large bird yokai saves him and brings him to a valley before Nyanko-sensei finds him. Natsume regains his voice after the group of yokai attack him in his room, and then returns the bird yokai's name.