I love the art, music, and even the controls and UI - this game has a really charming vibe where all its elements just come together really nicely! It feels incredibly polished, and details like monsters destroying the environment when you drag them really blew me away.
I did feel the pets turned into monsters very quickly, and it became immediately overwhelming with so many pets spawning over such a large area. I also struggled to understand what some of their needs were. The purchase bar on top also added another layer of complexity.
My advice would be to add a tutorial level that's exactly the size of the screen, where the player can get used to playing and meeting needs. That would also help with figuring out different needs icons, since the player would know whatever they need is already on screen, they just need to figure out what it is. Maybe even add pets that transform slower than others, to make things more forgiving.
I think this is a really engaging experience that even has room for expansion into a larger game, but it's confusing learning curve and overly-large map keep all of its perfect elements from setting into place. If you solved these two (through a small tutorial map or something else), I think this could easily make for a great and very enjoyable experience. Great work!