Three years after their breakup, Chae Yeong-in is shocked when her ex, Cha Seong-hyeok, the newly appointed CEO, reappears in her life. He casually admits that he came to see her every day, leaving her to wonder why he's returned, with more warmth and intensity than before at that. Seong-hyeok, the perfect man, and Yeong-in, the insecure « adopted » daughter, find themselves at a crossroads. Can they heal their past wounds and fill the voids in each other's hearts, or will their differences pull them apart again?