In the last ten years of the last decade, the alien parasite "corrosion core" brought by the "spore rain" has ravaged the world. The human survivors huddled in the "Iron Dome City" and relied on the "neural shielding ring" to resist parasites. The protagonist, Ling Mo, is a low-level investigator in Iron Dome City. His parents were slandered as "troublemakers" and executed for researching the Corrosion Core. He has been stigmatized since he was a child. After being infected with the Corrosion Core, he entered a "stasis period" and became a "symbiotic alien" between humans and the Corrosion Core.
