I love the void and I will cherish the void. Great job. Simple but well executed, perfect for a virtual pet game.
The one thing that I feel is lacking in the game are sound effects for petting and feeding the void. I know it's tricky to figure out what the void sounds like, but it does feel off when there is no audio feedback for my actions. Still since it's a void, I understand if you want to leave that slightly uncomfortable feeling in the game.
Again though, great job. I will forever be devoted to my little void.