Woah. I can totally see this game placing really high in the jam (though spooky might be a limiting factor), you did a phenomenal job implementing a unique and interesting game design. I adore the witty intro sequence, I read it all out loud in a weird accent, which I don't know how to feel about (It was a good thing). I love the idea that Jimi just has intermittent memory loss which completely warps his abilities. It was fun to try to keep up with different keys being the scream key, super creative.
I found the level length a bit long, and the ramp-up was slow (Maybe I'm just impatient). You could benefit greatly from more map layouts. The mechanics are really well polished, the animations are great, sounds are perfect. Brilliant execution!