How did the ancient emperors dote on their concubines?

Ancient emperors pampered their concubines by flipping cards, so that the overturned concubines could get the opportunity to spend spring night with the emperor.

In ancient times, the emperor, as a king, had three thousand rabbits. In addition to the queen, there are various side rooms with different titles, such as concubines, nobles, Jieyu and talented people. Because there are many concubines, it is a difficult problem to choose who to spend the night with, so there is a way of flop selection. The so-called flop is to choose one of the brands marked with concubines' names and engrave their names on the selected brands. Of course, historical records can be traced back to Sima Yan, the Emperor of Jin Dynasty. At that time, it was not a flop, but a sheep. When a sheep goes to a concubine's bedroom, it means that it will be with the concubine that night.