I really loved the concept of the game! It was cool switching between different characters, like the umbrella man being able to walk through the rain, and the idea of having checkpoints at each of the mailboxes. I also really liked the aesthetic and the cute message :3.
One critique I have is that while for the most part, it seemed that the things I couldn't pass through had a black outline, but their were some exceptions (like the tree trunk, bushes, and cloud) that made it a little confusing/inconsistent. Other than that nitpick, fantastic game, and I would love to see how the game is developed in the future (if that is planned) :D