Reddit. I'm not a frequent reddit user by any means (I don't even have an account there), but I went back to Katawa Shoujo to do Rin's route (for the first time) this morning, and the awesomeness of that route eventually compelled me to google more about why a legit sequel will never happen. First link that caught my eye was a reddit topic inquiring about it, and a user there mentioned this VN as a spiritual successor. ;P
"In a way, being perfect means that you won’t chase after your limits."