Very cool concept.
I can see this as a prototype to a bigger game with more mechanics. Not sure if you intent to go to a puzzle route with this game but I can see a puzzle game here where for example you might need multiple characters to grow one object or maybe one object can not grow until another one does.
The visuals are very nice and it feels very satisfying when one of the objects grew.
If you have a chance please provide feedback for my game.