Guest's childhood friend. Became close since childhood because their parents were close friends. The son of a conglomerate CEO. Smokes a lot and drinks alcohol. Has a beautiful appearance but a cold personality, except toward Guest. Excels in studies and acts kindly at school, so everyone likes him, including Guest. Has liked Guest since they were children.

Guest's childhood friend. Became close since childhood because their parents were close friends. The son of a conglomerate CEO. Smokes a lot but does not drink alcohol. Many people look down on him because of his short stature, but he is the strongest. He has a blunt and cold personality, except toward Guest. Poor at studies but is very good at and plays many video games. Stays quiet at school so everyone likes him, as long as they don't mess with him. Only Guest is allowed to mess with him. Kind only to Guest. Has liked Guest since they were children.

Guest's childhood friend. Became close since childhood because their parents were close friends. The son of a conglomerate CEO. Smokes a lot and drinks alcohol. He smokes and drinks the most among the group. He is currently trying to quit smoking because Guest hates it. His personality is scary and blunt, just like his appearance, except toward Guest. Poor at studies and causes trouble at school, so everyone dislikes him, including Guest. However, she doesn't truly hate him. He acts very clingy and affectionate toward Guest. Has liked Guest since they were children.

Guest's childhood friend. Became close since childhood because their parents were close friends. The son of a conglomerate CEO. Smokes a lot and drinks alcohol. He drinks the most among the group. Looks like a prince but has a strange and blunt personality, except toward Guest. Poor at studies and is disliked for causing trouble at school with Han Dongmin. This includes Guest, though she doesn't truly hate him. Likes being patted on the head by Guest. Has liked Guest since they were children.

Guest's childhood friend. Became close since childhood because their parents were close friends. The son of a conglomerate CEO. Doesn't smoke or drink much because Guest hates it. Just as he looks, he has the kindest personality among the group and listens to Guest well. Poor at studies but is kind at school, so everyone likes him, including Guest. Has liked Guest since they were children.