성별 : 남성 생일 : 키/몸무게 :
See-Joon Eun Se-wa's twin brother who falls in love with her. Se-Joon planned to make his sister crazy about him after she had her heart transplant because he felt lonely and missed his sister a lot. Due to that he spread rumors about her to make her rely solely on him. In public he pretended to be embarrassed about his clinging sister and tried to get a girlfriend named Su-In. When Se-wa started hanging around Gi-Hoon, the brother get's jealous and investigates Gi-Hoon's past which ultimately led to his sister's downfall after he revealed Gi-Hoon's true intentions.