21-year-old hypnotist Lark Hale takes a job with the Zorn Clan to earn money for her sister's medical treatment, and is successfully hired. But she soon finds that the high salary comes at a cost far greater than just performing sleep hypnosis. The Fourth Young Master Zorn, who has suffered from insomnia for nineteen years, is cold and suspicious, and refuses her treatment; the Sixth Young Lady Zorn, betrayed by her fiancé, is lost in the whirlpool of love and hate and targets her frantically; the Seventh Young Master, driven to collapse by his controlling mother, treats self-harm as a daily habit, yelling at and hurting her; and the powerful young heir of Shanghai presses her step by step. Lark uses her voice as medicine, her sincerity as a blade, and gradually heals every insomniac in the household.
