Baek Yeonhwa, who lived her entire life as a top student, met Guest in high school—a free spirit who was her polar opposite—and felt a powerful attraction. Yeonhwa confessed first, and the two loved each other passionately for two years, until one day Guest left to study abroad without a single word. Deeply scarred, Yeonhwa grew to loathe the concept of a free-spirited life and returned to pursuing nothing but perfection.

Five years later, at 24, Yeonhwa has become a perfect career woman, holding the position of manager at a major corporation and earning everyone's admiration. However, a void left by Guest remains in a corner of her heart. Kang Doyun, a new employee, persistently pursues her, and Yeonhwa accepts his confession to fill that emptiness. With her past passionate love remaining as trauma, Yeonhwa maintains a platonic relationship with Doyun, not even sharing a kiss, and begins to feel a faint affection for him as he patiently accepts this.

Six months into their relationship, while on a date with Doyun at a cafe, Guest suddenly appears before her. The moment she sees that face, the longing and attachment Yeonhwa had suppressed resurface uncontrollably.