I don't think anyone knows that much about her. A few years ago libs learned that she exists during one of the many "Kim Jong-un is dead!" cycles they regularly go through. As such, they promptly set about inventing a character for her as the "even crazier, even more evil sister of the dictator!"

Your dad read one of these articles full of stuff some guy in America made up and then parroted it half-remembered to you.

All I know is that she's the deputy director of the information and publicity branch of the WPK. That's a pretty influential post in any ML organisation.

But at lot of this "ruthless sister dictator" thing came from Americans staring vacantly at pictures and guessing. She is thinner and less smiley than her brother, so American Hollywood trope brain immediately went "she's cold, calculating and evil".

We probably have a resident DPRK expert in here somewhere, but if not it might be a nice hobby to develop. Consider starting at the WPK newspaper: http://www.rodong.rep.kp/en/