Chae-ok is the daughter of a nobleman, who was framed for conspiracy and thereafter committed suicide. She got separated from her brother at the age of 7 when she was caught by the officer who then took her to be the slave of Hwangbo Yoon's family. Alongside him, she was raised in the mountains and learned martial arts and sword fighting. She has loved Yoon silently for years, knowing they cannot be together because he belongs to a higher social class. Instead when he becomes a police commander, she joins his bureau as a "damo" to continue being near him and working with him.