Okay, this could be super fun, I want to see where this project can go!
As for art, the character gooks great, the saturation definitely takes your eye to the character. It isn't too colorful, and black being a main color does fit with the levels a bit. my only crutique of the character is that her animation for walking looks more like galloping or running with a limp, an extra frame in between 2 and 3 should fix that (I would think). I love the bubble buddies. They feel kinda like punching stands from jojo's, and I would want to know why/what they are in this world of levels. The little rolling frogs are adorable too.
Level design, the levels are simple, they feel like tutorials, which works, the coloring of the levels seems a little weird. I can't place it but the tiles seem unnecessarily dark. maybe my mind is wanting them to contrast more with the background, but I still like how much the characters pop.
You seemed to put a lot of time into animating and polishing the game. This is a double edged sword. It seems like most of these game jams are either like that, or have so much game that polish is an after thought. Though polished games, like this one, feel better in my opinion, I wonder how a longer form project would be managed. My game is rough, but I basically have the entire structure planned out, fixing bugs and adding flourishes are all I have left. But in yours I can see you adding lore and levels, but I have no idea where it is going. I love what you have, but I wonder what this game truly wants to be. As you continue to work on this (I think you should!) I hope you'll think on that, this game could be a lot of different things in it's current state.
PS: The song, it's very simple and short. I would have thought it would get grading, but It's still catchy