The amount of effort that went into this is very noticeable, and I think that's so cool! You built a whole world just for this jam, with a solid story, really cute visuals, cheeky text explaining lore, and a very consistent and well put together aesthetic. Fantastic!
The music here is all really nice and fitting. I like the choices you made with instrumentation, and how you correlated each instrument to the overall theme of your submission. The melodies are pretty nice, and everything sounds good. Nice!
The only "criticism" I'd give is that the level and boss themes feel a little too laid back. I think making them both a bit more busy, and emphasizing the tempo would've got their context across more clearly.
Big shoutout to the text on the youtube video, it's incredibly cute and quirky, and I liked it a lot.
Great job!