The World That Never Was
The World That Never Was (存在しなかった世界, Sonzaishinakatta Sekai?), introduced in Kingdom Hearts II, is home to Organization XIII, and is situated next to the realm of darkness in an in-between realm. It also houses the headquarters to Organization XIII, the Castle That Never Was, which is portrayed as a huge white castle decorated with the emblem of the Nobodies, in addition to Dark City, a deserted metropolis of skyscrapers.
The most distinct feature of this world is its seemingly eternal night, with the large, heart-shaped moon, Kingdom Hearts, continually shining in the sky. Kingdom Hearts was designed to appear as the heart-shaped moon from the cover of the first Kingdom Hearts game. When the scenario writer, Kazushige Nojima, created the scenario, he described it as a moon floating in the World That Never Was. Upon reading that, Nomura thought of using the visuals from the first game to create a connection.