Lucas, about to turn thirty and stuck in a rut, is shocked to discover that his younger sister was molested by a college classmate. Consumed by rage, he decides to kill him and begins plotting every detail of his revenge.
However, his plans take an unexpected turn when Eris, a mysterious blue-haired girl who seems to know his every move, appears. She promises to help him, but imposes one condition: he must pass three tests before carrying out the act.