First of all, five stars on audio and graphics. The bass guitar as sound effect is really cool and fitting with the hopping animation. I've always wanted to use musical instruments as dynamic sounds on my games too. The visual style is also on point and fits the premise and story really well. For some reason it reminds me of the movie Pi (1998). The tiny details on the background really add to the tone as well.
My only suggestion is that I died a lot early on, especially since the controls take some time getting used to. I would have made the player die less, with fewer obstacles or floors you can fall off of. Secondly, although I eventually figured out what to do, some clues in the dialog would have helped. E.g. Dumbo hinting that he/she has hands and can interact with objects.
Other than that, this was a really beautiful and poignant game and I'd love to see more of it. Keep it up!