It's a very nice concept
My two only complains are:
- the "controls" are appearing a bit too slowly, you often find yourself unable to move
- the theme is a bit too loose, as you can say that the controls/NPCs and the player are joined together for any existing game ever made. I don't know how to make it closer to the theme, but I feel it's not that far from it, maybe an additionnal mechanic could have done it?
Other than that, I appreciated it a lot, it's like a tower defense except you're the tower AND the thing to defend. Good job!