Who is prince Sado??
There's a famous story in Korea about this prince who is always commits violence and kills his subordinates who he thinks are not suitable for him, it all happened because he had childhood trauma and mental illness because of his father
Just to add onto that, it was his own father who "indirectly" killed him. He ordered him to climb into a rice chest, which was then sealed until he starved to death. It took eight days. The king saw him as too dangerous, but obviously couldn’t execute his own heir outright. There are some historical records which are even more unsettling, like how Sado reportedly stripped off his clothes before climbing in because of his fear of thunder, and how his wife later wrote memoirs describing both his instability and the politics around him. His son, (who became King Jeongjo), also tried to restore his reputation years later to varying degrees of success. There are some theories as to why he was so unstable and violent, which I won't get into here unless I write an essay lol, but if you're into history, I suggest you look it up! So much interesting stuff. Many “cruel prince” or unstable heir characters in Korean fiction end up loosely inspired by him.
I think all this cruel prince story from Joseon era who is have trauma and mental issues is inspired by the story of Prince sado, this is so sad actually