- The earth in the future has been reduced to a wasteland due to a catastrophe called the "Big Crunch". The catastrophe tore apart the real dimension, forcibly fused the earth with several different-dimensional space fragments, and released the "source dust" that transformed reality. This resulted in the extinction or alienation of 90% of all creatures into horrific "aberrants". The remaining human society collapsed, and the survivors huddled in settlements called "barriers." A small number of humans awakened superpowers called "visions" due to the radiation of the source material. Scientific and technological civilization has greatly regressed, and the knowledge and technology of the old era have become the most precious heritage in the ruins.
