This is one of my favorite entries, the graphics are on point, it gave me a luigi's manssion feeling, while the sounds were very serviceable, the story was also interesting without it being too intrusive, and the puzzles were really well design with the colors.
Suggestions:
-Having a many system right away so we are able to quit game or adjust sound and such would help a lot.
-Sometimes the areas felt a bit too big without them having any sort of meaning, instead tigther spaces with more details could be more interesting, and giving the monster a bit more personality as well.
-Story could be improved in the way its portrayed, maybe with some images, text and music, it would bring more impact to the moments.
-Some more polish.
Overall, is a great experience and very fun game.