This was a super unique idea, and its crazy to think that it stemmed from an offhand comment Cece made one time.
All of the systems at play here are super impressive and culminate in an awesome take on the theme!
The art, music, and writing are all fantastic, especially the twist with the final boss, I totally wasn't ready for that.
But I do think the combat can really weigh the game down at certain points. I had to cheese the Rissa fight by stepping in and out of her attack range, since they didn't spawn at the top of the room. I came to the comments to read the clarification you left on the rest notes, but it was after I finished the fight. Great idea, but if you don't know sheet music, that's not even something I would think you would consider, unless you noticed that the notes didn't do damage. I wasn't so lucky, and mostly just got caught ping ponging and stunlocked by the music notes until I realized you could walk out of her attack range.
Shiori had a similar issue for me, it was really difficult to weave around her projectiles, so it really just boiled down to me throwing myself at her until she died, since her health didn't reset.
I know the combat was intended to be difficult, which is fair, but it didn't really feel satisfying to finish off those two fights - I just wanted to get it done by the end.
I do think some slight i-frames or damage immunity after getting hit would help out a lot while still keeping the majority of the difficulty already present in the combat system.
I think I also somehow managed to erase the fat grem from every time period despite not killing him in any of them. Not sure if homie was just supposed to leave, but he peaced out for me and I couldn't finish the fight against him, which is small in the grand scheme of things, albeit a little confusing.
But otherwise I think this was an insane project to put together for the jam and deserves so much praise for its originality and unique ideas. Great work!