SPOILER WARNING!
I really enjoyed this game and very much liked the introduction to Japanese culture and the small 'reveal' at the end :)
It could certainly be longer and although it's quite professionally put together could do with some more polish, especially in the puzzle design. The writing is generally very good if a little clumsy in places, and there are some typos (Hayao-san is called Isao-san at one point, for instance).
Things like forcing the player to search a bin in a public place, or finding enough change in a vending machine to buy food, batteries, a talisman and a small box are clumsy and break reality a little. As does simply picking up a wrench and throwing it at a monster - could there have been something less incongruous at that location (or nearby) for me to neutralise the monster with? In Hayao's house, picking up the brush results in being forced to put it back down, while then going east results in being forced to pick it back up again!
At the end Hayao also tells you exactly what to do, it would have been good to figure it out a bit more.
There are some larger issues too, for instance as another reviewer pointed out, it's very easy for the library manager to start referring to a book that you never received. The reason is that you have to "talk to the manager" first, before then "asking them about" things, to which they refer you to the book they never gave you. The trouble is, if you previously talked to the Okami, the response suggests that "talking to" is not the correct way to interact with NPCs and you should "Ask about" instead. So you may well then not try that with the manager at all.
There also too much faff with containers, unlocking with a key, then opening to get things, and closing afterwards, etc. You shouldn't really have to close the torch after putting batteries in it for instance.
The tutorial is very good, I enjoyed that it explained things very simply but didn't force you to perform the instructions before allowing you to move on. One thing that occurred to me is that it would have been good to have included save and restore in the tutorial, (at the beginning the player has no idea how short and forgiving the game is going to be, of course), but I don't know whether that's hard to include in a multi-platform implementation like this?
Overall, I really liked the concept and the idea that objects, locations and characters are present for educational reasons and do not necessarily have any bearing on the game itself. I think with some more development it could be a really excellent adventure, and realise the full potential of trhe concept - I would love for Isao and Hayoa to have had to neutralise other yokai before completing the game, including the Kirin and the Akaname we discovered right at the beginning! :)