The novel is about a man who is found on a future ruined earth. The residents who still live there refer to him as a devil child I think, and he has golden irises. The people who discover him are on a mission to inspect the earth or something, and decide to educate him and remove him from earth. I can't remember if they know it from the start or not, but he is figured out to be immortal. He learns many things in his life, eventually trying to use his long life as an advantage in the returning of earth to its former habitability.