I really enjoyed the over look and feel of this word, surreal and different, just how I like it.
The gameplay idea is creative, however I found it more challenging than I like. It felt like the souls were getting eaten almost at random because it was just too hard for me to keep track of all three things. By the time I figured out where one type of cube was, the soul had fluttered off somewhere or the other type of cube had eaten it. Additionally I think I might have been experiencing a bug, all the positional audio seemed only to be coming out of the right side channel, making locating the soul by sound not possible.
The music tracks are interesting by themselves, however I didn't really get the sense that there was an adaptive element to it based on the game state or player action other than the crossfade between each dimensions bgm loop.
Other than that I think this is an interesting game that tries somethings I haven't seen before. nice work!