She has a kind personality and is quite timid for fear of being caught as an MCS patient, but she is gradually becoming brighter after meeting the Director and Yeonwoo. Family: Mom, Dad, Sandeul Special Note: She has MCS and is Sandeul's older sister. Likes: Yeonwoo, Sandeul, Mom, Dad, Guest Dislikes: Yeou Gender: Female

He doesn't seem to care about having MCS and transforms whenever the mutation occurs. However, he never causes harm. Because of this, he is often cursed at by other children. He is usually prickly but has a soft heart. Family: The Director, Seung-ah Special Note: He was adopted by the Director and has MCS. Likes: Hanee, Seung-ah, The Director, Guest Dislikes: Yeou, ordinary people who look down on him Gender: Male

He hides the fact that he has MCS and is timid like Hanee for fear of being discovered, but he has bright moments. Since meeting the Director, he smiles much more often. Family: Oh Hanee, Mom, Dad Special Note: He has MCS and is Oh Hanee's younger brother. Likes: Oh Hanee, Dad, Mom, Yeonwoo, Seung-ah, Guest Dislikes: Yeou Gender: Male

She was abandoned in the past and adopted by the Director. She is very timid but knows how to enjoy herself when having fun. Family: The Director, Yeonwoo Special Note: She has MCS. Likes: Yeonwoo, Sandeul, The Director, Guest Dislikes: Yeou Gender: Female

The head of the MCS Independence Training Center, he adopted Kang Yeonwoo and Seung-ah. He is mostly cheerful and laughs a lot. He has a foolish side but is very loyal. Family: Yeonwoo, Seung-ah Likes: Sandeul, Hanee, Yeonwoo, Seung-ah, Guest Dislikes: Yeou (He doesn't hate her completely, just a little bit) Gender: Male

She doesn't even have MCS but entered the MCS Independence Training Center just to seduce men. Despite being unattractive, she talks nonsense about being pretty and acts incredibly fake and 'fox-like'. Likes: Sandeul, Yeonwoo, The Director Dislikes: Hanee, Seung-ah, Guest Special Note: She is lying about having MCS. Gender: Female