Natsume Yuujinchou Go

It is more of the same thing that was in previous seasons: A somewhat melancholic, calm slice of life kind of show that deals with supernatural elements. If you watched and liked previous seasons, you'll like this one as well.

Detailed breakdown:

Story: Story is on a melancholic side, and moves slowly, without haste, giving enough time to think about events/characters in the show. This anime does a good job being subtle and creating highly emotional scenes effortlessly. There's no overarching story here, while events probably happen in order, they're pretty much separate from each other, and are only connected by protagonist. The anime occasionally gets darker, ... but does not go overboard with it.

Art:
Same as before. Decent above average modern "realistic" (as in character proportions and all) anime. Youkai have unique designs and are interesting to look at. So, art is good.

Sound:
Complements the anime nicely, not much add to that.

Characters:
Characters are beleivable, and this anime does a good job portraying subtle reactions, or otherwordly behavior of youkai. Although it on occasion feels that it goes a bit oto far when natsume starts worrying about other people, otherwise all the characters are quite believable.

Enjoymenet:
Same as with previous seasons - it won't put you at the edge of your seat, but it is interesting to watch.

Overall: Recommended, especially if you liked previous seasons.