This is The Visual Novel for me perhaps. I've started it more than ten years ago, got maybe three endings, and kept coming back to it but wasn't able to finish it until I looked into the source code tonight. It was epic. I especially liked your sensitive depiction of personalities through different manners of speech.

I couldn't finish it earlier because I had no idea which choices matter. I was even speculating that the words given in the 7 endings can be put together to form a sentence which tells you how to unlock a secret ending, something like waiting two minutes at a specific part of the script.