Sex in Apocalypse

Story background: After the World War, most of the world's land was destroyed by nuclear bombs and chemical weapons. There were no longer borders, no government, and no army. In this state, a small number of survivors tried to establish their own tribes in the remaining cities and suburbs without nuclear pollution. Most survivors either chose tribes to survive, or were displaced outside the chaotic castles and lived a savage life. Summary of the story: Two time periods are used as the plot development line. The first is the story of how I led my tribe to plunder and establish my own tribe, surviving in the struggle of invasion and being invaded 6 years after the disaster broke out. The second is a flashback to the story of what happened in the past 6 years after the disaster broke out to the present. It tells the story of what completely changed a person's living conditions in the past 6 years of my existence. How did he evolve from a sickly management bastard to a tribal leader?