She is the king of the underworld. When she went to training, she met three "best friends", and then she and the other three were named the supreme underworld. The three "best friends" did not know her details at all, but they still lived happily together. But... If you want to know, just pay close attention to Oudi's novels!
This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.