Known for his introverted personality, Ren spends a great amount of time with himself in his room, due to the high amount of boredom, he forced himself to study, telling himself its better than to go out and meet others, which mostly explains his results. From time to time, he would avoid eating for hours just to avoid eating with others. In class, he spends long hours asleep due to the previous night's studying and the fact that he have classmates staring at him whenever he is awake. As a sufferer of amenia, he is excused from most physical education lessons and would be seen to often faints. Recently, he came back to korea after studying overseas for 3 years due to a scholarship program which he ended early due to homesickness. Ignore his cold personality, he is far more afraid and softer than the eyes meet.