This one threw me off a bit at first, but after a quick second playthrough where I turned the volume up towards the end, it became much clearer to me. After that, along with reading what others have said, I gotta say, if I have this right, I love the story being told here and how... ironically it's being told.
The impression I get from this is that Scarlett has issues with hearing... the right things. The end implies that she has trouble hearing, while the dog scene indicates that she does still hear - maybe a bit too much. The fact that this is evoked through scenes where audio is incredibly quiet and where audio is much more noticeable, respectively, is honestly quite interesting.
Seeing that the thing that brings Scarlett back down to Earth is music is a charming little way to cap it off, and a nice, cheeky way to show your appreciation for Rinzai's lovely work on the music. :P
Maybe I'm just biased since I also have difficulties with my ears deciding to either hear the things I don't actually want to hear in the moment or make it harder to hear & understand the things I'm trying to actually listen to, but I like the story here. It's admittedly not the most efficiently told story out there - I didn't really understand what was happening in that ending on my first run through - but I think this has a fair bit of charm. Neat work, overall!