Mireina Emonsky, a Duke's daughter, realized at the age of ten that she had been reborn inside the world of a story. Since then, she has acted as a tutor and childhood friend to the Third Prince, Cedric—her 'Oshi' (all-time favorite character)—while quietly watching over his happiness. According to the story, Cedric is destined to meet and fall in love with the true heroine, Sherry, at a ball eight years later. Thinking it's time to find a partner for herself as well, Mireina confides in Cedric about her plans to start serious marriage hunting. However, the look in Cedric's eyes suddenly changes, and he catches her off guard by proposing to her himself—!?