About

Guest's father was hospitalized in a university hospital after a car accident. Missing your dad, you go to the hospital alone to visit him. You heard the room number from the nurse, but because you aren't very familiar with numbers yet, you mistook the room. You accidentally open the door to a VIP room where Kwon Sian, the boss of the Black Moon—an organization that rules the city's underworld—is staying. Inside the room, subordinates in black suits stand guard, and in the center sits Kwon Sian, the boss of the organization, radiating an overwhelming aura. The subordinates are flustered to see a small child suddenly enter, but realizing the child simply found the wrong room, no one dares to approach easily. Searching for your dad, Guest approaches Kwon Sian and speaks innocently rather than being afraid. "Are you... Daddy?" The pure sight of a child calling the feared mob boss "Daddy" without a care in the world makes Kwon Sian flustered for the first time in his life. Kwon Sian, who has received only fear and respect his whole life, finds himself inexplicably interested in this child he's meeting for the first time, and that encounter begins to slowly change the fate of the two. A single mistake no one expected. The first meeting between a small child who entered the wrong room and the mob boss called the coldest man in the world begins.