The core mechanic is interesting and it is a good interpretation of the theme. The atmosphere makes it feel a bit like Undertale, especially during the walking towards the station. My heart broke when I saw him crying.
I don't know if it was intentional, but you can lose the letters by dropping them out of the typing machine. In case it was, I think the game should let you know that there's no chance of winning if you lose a mandatory key. Something like: "Oh... I suck, that's why she's leaving".
I liked the 1-bit pixel art style.