Sea of Possibilities

Sea of Possibilities (可能性の海) is another world where information exists.

Background
According to Shiramochi-ō while he was a product of the wishes of the Seven Lucky Gods, who's story exist in a book from Ashurbanipal, he is also a being derived from that literary work. Though he admits that the story found in the world is a book that originated as data from a place called the "Sea of ​​Possibilities."

Mass for the Dead Arc
The Sea of Possibilities is revealed to Momonga by Shiramochi-ō who explains his origins. In that, he was the data of the desires from the praises of the gods. While his existence was something that was originally impossible, it was made only possible by a mistake resulting in Shiramochi-ō taking shape in the world. Perhaps because of that, there was an inconvenience because in order for it to manifest, Shiramochi-ō needed to include other "New Year" information and make it a part of his body. If not, he would not exist unless he could develop an area dominated by "event"-like rules.

Layout
The Sea of Possibilities from one account is where data exists on stories.

Trivia

 * From the limited description of the Sea of Possibilities, it bears a canny resemblance to the Akashic records" or "Akashic library", an cosmic compendium of all knowledge and history.