The Villainess Ruler

here exist a ruler... who was a villainess. Everybody feared her, her abilities, power, and absolute control. But not also that., because of how insane the royal family is. That anonymous ruler also has an unknown gender. No one knew if it's a female or a male. But no one from the aristocrat has dared to tell their ruler to remarry nor have a concubine. Because they are all cowards. They feared that their ruler will start a war once again. Their first grand war was all because of their ruler's anger because of the betrayal of its lover. And that time, everyone thought that the hell was empty... Because the demons are on the throne, reigning fear on the living.