I legendary place that exist but also doesn't exist. You can find any information and history here, even if something completely erases it. It once was a regular library that existed in the ancient kingdom that once stood where Crescent Woods now stands. The librarian that was working there sold her soul in order to gain knowledge, granting her the ability to host the White Library. Which is now located in a void of non existence.
No one knows how to enter it. Yet Leo has entered multiple times.
Thousands of years ago, White Library was in the ancient crescent kingdom that is now known as Crescent Woods.
It's current location does not exist.