Mi-young (Song Eun-jin) returned to Korea, longing for her unattained first love, Jae-hyuk, whom she met during her studies in the U.S. She discovers Jae-hyuk is now dating her sister, Mi-hye (Joo Yeon-seo). Despite Mi-hye breaking up with Jae-hyuk to respect Mi-young's feelings, Mi-young struggles with her unresolved feelings. Months later, they reconnect at a funeral where Mi-young finally expresses her love for Jae-hyuk. Meanwhile, Mi-hye cautiously begins a new relationship with a divorced colleague, Young-hoon (Kim Do-jin).