It was an extremely cruel story, but as it would be a problem if it was leaked to the society that the king’s younger brother took pleasure in mass murder, it was eventually decided to get rid of that royal prince by pretending him having died of sickness.
But then, thanks to that secretive disposal, the wrath of the killed people permeated the mansion and grounds and ended up accumulating there.
Nowadays it seems to have changed into a disaster class flawed residence even the church gave up on.