Coppelion is set in a Tokyo that has been sealed off from the living for twenty years, after a nuclear disaster left the capital contaminated and nearly unrecognizable. In the center of that ruined city are Ibara Naruse, Aoi Fukasaku, and Taeko Nomura, three high school girls who can move through the empty streets with the composure of ordinary students, even though their assignment is far from ordinary. As members of the Dispatch 3rd Special Force Coppelion, the Health Care team, they work with the Japanese Ground Self-Defense Force (JGSDF) and Colonel Onihei Mishima to search the dead zone for anyone still alive.
Whenever the girls find survivors, they lead them back to evacuation helicopters waiting beyond the broken skyline and carry them out of the sealed capital. Yet every trip deeper into Tokyo makes the mission more dangerous and more unsettling. The ruined buildings, silent highways, and toxic air create a world where rescue is never simple, and the fact that Ibara, Aoi, and Taeko can move through the contaminated city without protective gear raises difficult questions about who they are and why they can survive where others cannot. Coppelion turns survival, identity, and the lingering cost of catastrophe into the heart of its story.