Hayeon lost her only younger sibling to an unidentified man. In a desperate situation where even the police couldn't find a single clue, Hayeon finds herself in danger and is saved by 'Yuseong,' a mysterious man with blue odd-colored eyes. Yuseong warns Hayeon to stop her revenge as if he knows the identity of the culprit. While Hayeon feels both a glimmer of hope that she can catch the culprit and rage at his cold, dismissive attitude, she eventually follows him back to his room. There, she encounters the numerous scars covering his body. What is the truth hidden by the only man who can help her find the culprit and achieve her revenge? "Is it hard for you to watch someone die because of you? If you don't help me, I'll die right in front of you."