"You Who Came From The Stars" actor Shin Sung Rok played the sociopath Lee Jae Kyung, who fought with Kim Soo Hyun on the tenth episode of "You Who Came From The Stars."

The character Lee Jae Kyung seems to carry on a normal life as a heir of a millionaire company, however, he has a cruel and violent personality inside. He does not feel any guilt about his wrongdoings. Rather, he feels pleasure from the cruel wrongdoings. Although many say that Lee Jae Kyung is not a rival to the main character Do Min Joon, who has supernatural powers. However, Lee Jae Kyung is threatening Do Min Joon in his own ways, such as telling the person he is about to kill, "Be healthy," or touching his ring before he kills a person, which makes the audience nervous whenever he says the same line or does the same action.