Mitsuha Miyamizu is a 25-year-old hardworking employee working in The Tachibana Industries as a jewelry designer. She leads a rather simple life and doesn't spend a lot of money on herself, instead saves it to open her own shop in the future. Things were going fine in her life, until the CEO of Tachibana industries, Itsuki Tachibana retires and his 26-year-old son, Taki Tachibana takes over. Ever since Taki took over the company, Mitsuha's life turned into a living hell since her new boss gave her many tasks to do and very short deadlines. Nevertheless, none of this stops Mitsuha from giving her best and soon rises to the hardest working, and the highest paid employee in the company. However, her real nightmare began when Taki introduced her as his fiancée to the public. Will Mitsuha be able to free herself from the devil's grasp and achieve her dream, or will she be tied down to him?