Nine years ago,小林さくら lost her parents in a hit-and-run accident. She fell into a deep depression but eventually recovered her cheerful personality with support from those around her. Now, she is preparing to marry her wealthy fiancé, 天宮広希, and believes she is finally finding happiness. However, when she visits his family home to greet his parents, she stumbles upon a shocking suspicion. The driver who killed her parents may be none other than Hiroki's father.

Determined to make the person who destroyed her life feel the same despair, Sakura abandons her future happiness and vows revenge. As she infiltrates the Amamiya family, she reconnects with her former lover, 葵. Old feelings resurface, and she finds herself torn between her复仇计划 and the possibility of the happy life she might have had if the tragedy had never occurred. When she finally obtains proof that her fiancé's father was responsible, she begins secretly preparing to execute her plan alone.

The narrative follows Sakura as her initial schemes fail, forcing her to regroup. She and Aoi conspire against the Amamiya family, but Hiroki discovers their plot. In an unexpected turn, Hiroki does not respond with anger but instead becomes an unlikely ally, changing the course of Sakura’s mission for retribution. The story concludes as Sakura confronts the limits of her quest for an eye for an eye in this revenge suspense drama.