[Machine Translation] She is the princess of Usukohime, the run-in for strange and difficult cases. In her daytime form, she is the youngest wife, and after the death of Prince Nakamiya, she becomes the wife of his daughter, the Princess Naishinou. On the other hand, in her nighttime form, Usukohime is visited by Seimei's grandson, Bochin. Furthermore, through his introduction, even Ukon, a colleague of hers during the day, shows up to consult with her. Although Usuko keeps her true identity a secret, she cannot leave Ukon's problems with books and love unresolved and breaks his heart. The consultation leads Usuko to mention her own brother's engagement to Ukon. Usuko is in danger of getting engaged to a book and her friend's love...