Introduction: This is a world only for men. Those who have red palace sand near their navel can conceive children. Those who don't have it are pure men. In terms of appearance, there is not much difference between the two. To distinguish them, men who can have children must grow their hair long and have their ears pierced when they are 3 years old. At the same time, they cannot go to school, join the officialdom, or join the army. They must learn from their father to run a household and learn to care for their children. They reach adulthood at 16 years old, and pure men have to be 18 years old later.