The National Library of Elchea (国立エルキア大図書館, Kokuritsu Erukia Dai Toshokan) is a luxurious library where millions of books are stored, most of which were collected by Jibril. Sora described the exterior of the building to resemble the Library of Congress, located in Washington, D.C.
Inside the library, there are bookshelves piled up against the wall and ceiling, inevitably defying the laws of gravity. There are numerous light orbs floating in the air and bookshelves that were tens of meters tall, constructing a maze-like situation filled with a fantasy-like atmosphere. It also contains a fully stocked kitchen, and the equipment to conduct a game of Materialization Shiritori.
The library was originally controlled by Imanity, but was lost to Jibril through a game. Sora challenged Jibril for the right to own her (and thus the library), and won, thus Imanity once again owns the library. Sora allows Jibril to continue her use of the library, and gave her the books stored in his tablet that she had bet for. Jibril now manages the library, which college students and any literate person can come to use.