How would the emperor punish an ancient concubine for cheating? These punishments are surprisingly "merciful"!

You are wrong about this. In ancient times, concubines were not allowed to cheat. If they cheat, it will be a secret execution. It's just that it's a secret that I killed you. The pain of killing you is unacceptable to ordinary people. In ancient times, Xiban had no cabinet, but many of them were basically widowed, that is to say, he had no contact with anyone from the time he was attacked to his death.