In 2175, humans built a high wall, and the world was re-divided into several major jurisdictions, under the jurisdiction of the highest organization HPO (Human Completion Project Organization). What is isolated outside the wall are not external human natural enemies, but the consequences caused by humans themselves, radiation, mutation, pollution, and civilian areas where people who are close to the high wall and cannot enter the wall gather...
As extremely rare native humans with complete human original genes, Phoebus and Erebus are declared to be an epoch-making pair of twins. In this era when the natural fertility rate has dropped to negative numbers, this seems to represent some kind of hope...
But as it was said in that drama many years ago - each of us has an unknown side. On the one hand, he wants to save the world, and on the other hand, he wants to take care of the people he loves. These two aspects conflict with each other, and this is the so-called torture of the soul.