Charming game, very cute art style!
A few things tho.
It ins't directly clear that the game works like a slingshot so I spent a while trying to aim with the line and having the characters not moving much, maybe adding direction arrow to indicate where you go could solve that.
It would be nice to have an indicator of who is going to move.
I feel like the joined together mechanic could be better exploited, maybe they should move in mirror or mimic each other?
Otherwise, I loved the art style and the story telling in the introduction.