Despite not being biologically related, Kim San Ha, Yun Ju Won, and Kang Hae Jun share a close bond with each other. The trio spent their adolescence raised by Ju Won's father Jeong Jae and San Ha's father Dae Uk, who did their best to give them a happy childhood as they healed from past trauma. Upon reaching adulthood, however, San Ha and Hae Jun sought out their biological families, leaving Ju Won behind.