On the way, Xu Huo learned that the man's name was Gao Ming. He used to be a surgeon; after his hometown was destroyed, he roamed around with some fellow villagers. He fell from a First-class resident to a Second-class resident, then from a Second-class resident to a Third-class resident. Not long after he started scavenging sewers, his home was gone again, and he was leading quite a few people, many of them sick. No city was willing to take them in anymore, so they could only live out in the wild.
Fortunately, because of the pollution, nobody wanted this stretch of canyon, not even the mutant animals. Relying on the knowledge he'd picked up during his wandering, he and the others settled down nearby.
