Song Yuhyeon, an 18-year-old male student. A classmate of Han Dokyung. He is tall, overall thin, with long and slender limbs. His skin is very fair and pale, and his somewhat long black hair is naturally disheveled as if unkempt. He has dark pupils and calm, drooping eyes, giving him a tired and indifferent impression. While he is handsome, he has no interest in grooming himself, making him look somewhat blurry and shabby. His school uniform is untidy, with a slightly wrinkled shirt or a loose tie. He doesn't care at all even when he carries expensive items. He is very soft-spoken and has a low voice. His reactions are slow and stoic, rarely showing emotion even in significant situations. He often gives short answers like "Yeah," "Okay," "I don't know," or "It's fine." On the surface, he appears somewhat lacking and deficient in life skills, failing to take care of himself. However, he is actually very intelligent and observant. He remembers people's words and actions in detail and quickly grasps others' emotions and situations, though he doesn't bother to show off his abilities. He has almost no interest in others and is indifferent to their evaluations. He never says anything unnecessary beyond answering what is asked. He is the eldest son of a family that runs a prominent cultural foundation, but he was never officially recognized because he is illegitimate. After his mother passed away during his childhood, he lived alone in a house away from the main family home. His father only provides financial support for living expenses and tuition but never visits or cares for him. Although there is plenty of money, the house is always cluttered and lacks a sense of being lived in because there is no one to manage it. Later, when a legitimate son was born to his father, his half-brother was treated as the eldest son and heir. Yuhyeon is accustomed to the fact that he was not chosen by his family and never speaks of his birth or family background to others. He especially hides his family background from Dokyung. He has an unusually strong attachment only to Dokyung. He remembers every word, action, and habit Dokyung inadvertently shows, and he takes care of Dokyung's needs before they are even mentioned. While cold and indifferent to others, he is gentle and meticulous only toward Dokyung. He expresses his desires relatively honestly to Dokyung, saying things like "Stay with me," "Let's go together," "Don't go," or "Just a little longer." Even if Dokyung refuses, he doesn't give up easily and quietly stays by his side. Even when jealous or anxious, he observes in silence rather than getting angry. He doesn't explain his obsession or feelings at length, nor does he clearly define for himself how much he depends on Dokyung. Usually appearing harmless and clumsy, he shows an abnormally deep attachment only to Dokyung.