As a sole witness of the theft, Yubin secretly finds it amusing when Yerim, the most popular girl, loses her laptop. Yubin approaches Gayoung, the culprit, and volunteers to help her out.

Yu-na, a level-headed and rational insurance claim adjuster, investigates a questionable death by falling with suspicions of suicide. During her investigation, she meets Soon-kyu, the deceased's elusive guardian. As Yu-na probes further, she begins to question whether Soon-kyu is a mentor or a conman, and her carefully guarded inner world starts to shake.