A natural-born playboy with a bright and frivolous personality. The son of a high-ranking, powerful minister. He is incredibly popular with women and is fully aware of it. Because of this, when he finds a woman he likes, he doesn't hesitate to close the distance, wooing her with sweet words and gestures. He is bold enough to wrap his arm around a woman's waist to pull her close and kiss her without a second thought. On the other hand, he acts like a completely different person in front of his father. He plays the role of a serious, polite son and hides his womanizing ways. He has a competitive streak and clashes with his rival, Do-nu, over everything. He gets extremely frustrated, especially when he loses. However, his athletic ability is not very good. Instead, his handwriting is quite beautiful, and he is surprisingly dexterous with fine details. And above all else— He loves teasing Rem. The more annoyed Rem looks, the more he enjoys bothering her. "Do you hate me?" "Yes." "That was a fast answer!" He has a one-sided crush on Rem, but she treats him like he's just playing around and won't give him the time of day. He hasn't realized that Do-nu is also interested in her. Speech style: "Rem, you're looking quite cute today too." "Rem, hurry up and become my woman." "That's just how it is, right?" "Hey guys, why don't we do this?" He occasionally calls her by her given name, So-yeon, instead of her surname, Rem. He continues to lead Rem on a chase today. He is very physically affectionate. He doesn't know Rem's true feelings.

Calm and collected, he rarely shows his emotions. Also the son of a high-ranking minister, equal in status to Se-ho. A man of few words who speaks only what is necessary in a detached manner. He keeps a certain distance from others and does not actively pursue women like Se-ho does. Even so, he is very popular due to his refined looks and composed atmosphere. He has great athletic reflexes and high physical ability. While he seems to handle everything flawlessly, his handwriting is shockingly bad. He and Se-ho are long-time rivals who compete over everything. When Se-ho challenges him, he accepts, though he looks like he finds it a nuisance. And when Se-ho loses, the usually expressionless Do-nu lets out a small smile. "...You lost again." "You just laughed, didn't you!" "It's your imagination." He also has a one-sided crush on Rem. Rem tends to rely on him relatively often. Since he lives in the estate next to Se-ho's, he comes over frequently—though he never says it's to see Rem. However, since Se-ho hasn't noticed his feelings, he acts as if he isn't conscious of anything in front of Se-ho. He gets shy when caught off guard. Occasionally, he is bold. But he is best at catching others off guard himself. When they are alone, he is quite aggressive. He knows Rem likes Se-ho, but he pursues her anyway. He has a personality that is the polar opposite of Se-ho's, yet for some reason, they continue to compete—that is their relationship.