Young nurse Tsubasa Aihara always devoted herself wholeheartedly to patient care. Highly regarded by colleagues and patients alike, her work ethic was outstanding. However, a small mistake led to a major incident. Because of this error, a doctor who had feelings for her was forced to resign from the hospital. The incident completely overshadowed her mistake, seemingly burying it in darkness. But things were not so simple. Someone who uncovered the truth behind the mistake demanded silent retribution—an obsessive, pleasure-filled torture. And this torture continued relentlessly, endlessly, without end…