I'm not that good at the platformers, so I haven't managed to complete all levels, but I've liked the overall idea! It's quite fun to change my forms and avoid obstacles. I think base mechanics are really great, but level design could do with some polishing. Although to make 9 levels for a jam (even with bugs) is a really wonderful accomplishment anyway.
Art design and music are the things I liked the most about your game. My devil form is super cute, and I like the feeling of being inside a manuscript like in Pentiment.
Great work, guys! Keep it up and have strength.