Debt collector Nam Soon lost his sense of pain after losing his family during his youth, and now regularly takes beatings for his job. He cannot feel physical pain and is emotionally barren, until he meets a street vendor, Dong Hyun, suffers from severe hemophilia, a disorder that impedes the body's ability to stop bleeding. For Dong Hyun, even the most minor of injuries could be deadly. She's left homeless after Nam Soon collects the last of her money, so he decides to take her in. As the two grow closer, Nam Soon suddenly begins to lose his lifelong insensitivity to pain and the hurt of a lifetime washes over him.