The Expanse, also referred to as Makai (魔界?, lit. "Demon World", or 魔階?, lit. "Demon Plane"), is the world/dimension where demons, spirits and other types of supernatural entities reside in the series. The most accepted translation of Makai means Demon World, and it is sometimes referred to as such. In the original Digital Devil Story novels and in Shin Megami Tensei: Strange Journey, this plane is referred to as Atziluth.