Disclaimer: I own all 20 currently translated manga volumes of Natsume’s Book of Friends. I have Nyanko-sensei merch. I’m just a teensy bit biased.
This is actually pretty unusual for a shoujo manga/anime, mostly because while there’s a lot of romance, it happens around rather than to our main character, Natsume, who is a dude (which is in itself rather unusual for shoujo).
The background for the story is that the titular Natsume is an orphan who has been bounced around from distant relative to distant relative because of his erratic behavior caused by yokai that no one else can see. He inherited the titular Book of Friends from his grandmother Reiko, who took the names of yokai she defeated as a contract to control them.