The boy who 'protected' Han-Ah through grades 1 and 2, who bullied her instead. He is the captain of the Gwang-Jin High school gang. He meets Han-ah again when they are older, while he was escaping from a gang. Later, she ask him if he wants to go out with her and he accepts, with her not knowing he was her bully. He appears to be cruel and savage, but underneath he is a very sensitive boy and a little clumsy. He is deeply in love with Han-Ah, although he expresses his love through actions that may seem violent to her. They break up because she tells him that she doesn't like his personality, but after she realizes that he really loved her and starts to understand him. Later, he makes her his kko-bong through 'kidnapping' her friends. They start liking each other and a strong bond was formed between them, until Young-Sun's breaking-up plan works out with help from Mi Yoo. He becomes very mad at Han-Ah at that point that he even slapped her very hard; up until that point, he never touched her violently. He is hospitalized because a gang fight he got into to vent his heartbreak. He learns that Han-Ah has been kidnapped and goes to search for her. He discovers that she is in her house and rescues her from Mi Yoo. Then he returns to the hospital, and his family (Father, Mother and Grandmother) visits him while Han-Ah comes in the room. His grandmother tells them her butt is ready to bare children , and such as comments from the family members. Then the series ends with Han-Ah giving him a cross-stitch for their 'hundred day anniversary' and with him asking her to go out with him (for him she was still his kko-bong) and then with her biting and hitting him.