Kim Misun is Seungmin's sister. She is one of the staff members for Stray Kids and helps with the make-up and clothes designs. As Misun works for Stray Kids she finds that she starts to love them like family. She travels with them wherever they go and makes sure that each member gets everything they need. From going on tour to just dance practice she makes sure everyone has everything they need until one day she needs them to help her.