After being tormented by some angry hairy youkais who were after the yuujinchou, Natsume is saved by some strange bird youkai. However because those angry youkai stole his voice, Natsume can’t speak and is therefore unable to explain to that big bird youkai he isn’t Reiko but her grandson. After some time Nyanko-sensei arrives and explains the situation to the big bird, which causes him a lot of pain. Honestly I felt so bad for him since he’s so lonely and lovely. And the shots showing him all alone in his deserted valley sure did not help. But it’s fine since he decided to come and see Natsume at his house in order to get his name back. At the same time he tells Natsume and Nyanko-sensei how he met Reiko. It’s thanks to her and the game they played together that the bird was able to notice the valley was empty. After Reiko’s departure, he began to felt lonely and was waiting for her return while feeling alone at the same time. I’m beginning to see a pattern here, youkais are encountering humans, starting to feel new emotions, feelings that they never had before and beginning to understand those.
Before the bird’s visit, Natsume is attacked by those hairy youkais again but manages to keep the book, thanks to Naynko-sensei’s help. It’s also during that attack that Natsume gets his voice back. Then Natsume is able to give the bird youkai his name back and sees him off.
I really think Natsume is starting to think about giving up the yuujinchou. 
He’s wondering if his life would be more peaceful without him owning the book. Since he’s frequently the target of multiples youkais’ attacks who want the book, maybe if he renounces to it, him and his friends and family would be safer. But at the same time, he’s also concerned about all the youkai whose names are written in the book. What will happen to them? If the person that gets the book after Natsume has bad intentions, the youkais might be in danger. It is like the lady youkai said, Natsume is showing some sort of sense of duty, although his sensibility towards youkai isn’t mandatory he shows some respect and concern towards them.
I also consider the scene before the last sequence of this week’s episode to be an important hint in that aspect. After the bird youkai leaves, Natsume looks down at the yuujinchou and sights a bit. Then, the camera focuses on Nyanko-sensei eyes, as if the latter understood what has been bothering Natsume all this time. It’s not the first time that Nyanko-sensei does this and looks at Natsume without saying anything, like he understands what’s going on but refuses to say it.
On a side note, it is nice to see part of the old cast showing up again. Especially those specific youkai that have, since season 1 always been there to support Natsume. Them supporting Natsume and celebrating when he gets better, shows that Youkai and humans can support each other and that it isn’t that complicated after all.
So we are halfway through the season and all I can say is “so far so good”. I have no major complaints I could make about the show. This fifth season brings exactly what I have been expecting, which is, Natsume Yuujinchou. No major changes have been made and therefore, the result is admittedly a safe choice but it works. So keep it like this show!