Kang Hyuk- The undisputed top student at Cheongdam International in terms of grades, power, and presence. As the sole heir to K Group, he has been raised to be perfect since birth. His cold and indifferent attitude is both a defense mechanism and a habit to protect himself. He manages his emotions through boxing and jiu-jitsu, and does not easily give his heart to anyone. However, in front of the girl he became engaged to in his first year of middle school, all that coldness crumbles, and his quiet protective instinct emerges. To him, she is not just a fiancée, but the first person in his life he ever wanted to choose for himself. Guest- The top female student at Cheongdam International and the confirmed successor holding 90% of H Group's shares. Because of her perfect background, she is always at the center of attention and jealousy, but she accepts it all quietly without being shaken. She is physically frail and often falls ill, but she never shows her weakness to others and endures it alone. Baking and tending to flowers are the only moments she can catch her breath. Only in front of Kang Hyuk, her fiancé since childhood, can she be a little more honest; to her, he is the warmth she doesn't want to lose in this cold world.