In the beginning Hye-Mi appears cold, prejudiced and presumptous but it is revealed she is quite vulernable and lonely inside. Her arrogant and nonchalant attitude lead to many of her misfortunes. She viewed pop music and those around her as third-rate and 'not worth her time'. With the help of her friends and others around her she slowly recognizes her faults. Hye-Mi grows into a much more expressive and caring person. She learns to become more open minded and hardworking. Hye-Mi becomes respectful and kind to those around her although occasionally retaining her arrogant nature that hides her change in character.
- Early Life
As a young child she met Jin Guk (who was then Hyun Shi Hyuk) and became very good friends with him, it can be assumed their friendship was short lived as Hye-Mi didn't recongnise him when they were reunited.She is originally from a wealthy family but after her mother ran away with Kang Oh Hyuk, her father's business went bankrupt and became very heavyily indebt to the loan shark, Ma Doo Shik. She is initally pursued by Ma Doo Shik and his men.
- Events of Dream High
Hye-Mi is striving to study classical music at Julliard School in the United States when her family goes bankrupt and becomes indebt to Ma Doo Shik. Hye-Mi is chased by Doo Shik and his men and at one point forced to sing at his nightclub. Later Doo Shik makes a deal with Hye-Mi to pay off her family's debts. To pay off her family's debts Hye-Mi agreed to enroll at Kirin Arts Highschool so she can one day debut as a singer.
Initially Hye-Mi pretends to have feelings for him so she could get him to attend Kirin Arts Highschool but eventually Hye-Mi develops feelings for him athough she tries to deny it. She attempts to convince herself she doesn't have feelings for Sam Dong but in the end she can no longer deny her feelings. In a short cameo in My Love From the Star, it is revealed that Sam Dong is now her ex-boyfriend and that she was interested in Do Min Joon, her professor who is played by the same actor that played Sam Dong, because of his appearance.
In the beginning Hye-Mi and Baek-Hee were best friends also this friendship seemed unrequited. After Baek-Hee is picked at the Kirin Arts Highschool audition over Hye-Mi, the two become bitter enemies and rivals. Slowly over time Hye-Mi and Baek-Hee settle their differences and rebuilds friendship.
Jin Guk was a childhood friend of Hye-Mi. She liked him before she realized her feelings for Song Sam Dong. Hye Mi tried to convince herself that she liked Jin Guk in order to forget her feelings for Sam Song Dong.