I have to admit that I read this one before reading the ones before it so I may be missing something. However, we have further interactions with Natsume and Matoba. Again, Matoba tries to coerce Natsume into joining his group who are ruthless and holds yokai in distain. Natsume is persuaded to help Matoba against the lastest Yokai threat but must decide whether the safety of those he love is worth joining Matoba.
In the end, it is the same cycle with Natsume. I think why I keep coming back and reading each adventure is that I really love how Natsume is able to stick to his guns realizing that his position is an extremely difficult and ungrateful one. He straddles the worlds of the humans and yokai which seem at odds with each other all the time. Each adventure is a test for Natsume where we are happy when he triumphs.