This game is a Binksi game, which uses minimal pixel art and animations to create an environment for narrative storytelling.
The story told here is about a shut-in whose depression is keeping them from finding enjoyment in any of their previous activities.
But then checking the mail reveals numerous messages from an anonymous penpal. The sustained communication from a stranger provides some solace.
I've seen this effect before in real life; I've definitely benefited from regular contact with people I don't even know that well. So I liked that part. Some of the story really stretched suspension of disbelief though; I wonder if simulating a longer time period might have worked better, even without additional words (like having it get dark and light again each time you get a letter).