This was a really neat visual novel! I feel like the gameplay is a little tedious though. As pickled peanuts mentioned, right at the end of the subway is when it starts to feel less engaging.
Because of this and in addition to other things, I've only found two out of four of the endings and I'm not sure how I'd unlock the others because of the limited interactivity in the game.
In the subway, I'm not sure if so much of the graffiti is supposed to say (something along the lines of) "This looks like very old graffiti" when you examine it. Also, I'm not sure if you're supposed to be able to read the scripture written in kanji in the second-to-last level. It takes up a big portion of the wall like the text in the movie theater did, but there's no way to examine it and read the contents of it if you're an English speaker. Also, around this level and the one after it feels like performance and framerate dropped significantly—and I actually own a really beefy computer. That could have been a figment of my imagination though.
Overall, I still liked it however! Thank you very much for making it. :)