Natsume Yuujinchou - the poor man's Mushishi.

On a paper, the concept looks good. Youkai are great source of inspiration for a story - their variations can lend to a distinct feel and even their most basic form appeal as something unusual to a western reader. Sadly, it's something you can keep milking only for so long if you don't improve the staleness of the story itself. Yes, the main weakness of Natsume Yuujinchou is that it's going on for way too damn long without much change of variety. Yes, it is episodical, but unlike the forementioned Mushishi that is still highly creative with it's variations of the self-contained stories and which produces a sense of emergency and danger for the characters, Natsume is just... too mild. The only thing that changes is the design of youkai, otherwise most of the arcs are "Hey it's me ya boi youkai of the week, I will now bother you for a while in relation to your grandma until we come to agreement". I hardly ever felt any of the characters were in a real danger as the series seems to love it's status quo. Thanks to the protagonist being anchored in one place instead of travelling around, it is harder for the small arcs to end more drastically for the secondary characters as that would change the setting around the protagonist noticeably, which is something this manga is not exactly willing to do.

The plot is repetitive to a point that I would even call it boring. And as a larger problem, it feels like it's just backtracking a non-existent prequel of the past adventures. I would rather read a manga about Reiko and the start of all those stories than the clean-up after them. Most of the cast is forgettable and the only reason the protagonist and the cat aren't is because of the count of their appearance, but they too don't offer much of engaging character traits. The art is not bad for a shoujo and as mentioned I like the youkai designs which are the best part of this manga.

If you want an episodical work with youkai central to the plot, go watch/read Gegege no Kitaro instead. It's actually more fun and more creative.