Perdi, a widely renowned adult novelist, is actually Vivian, acting as the Imperial Night Librarian. Upon submitting the fourth draft of her latest novel to her publisher for review, Vivian receives criticism on her portrayal of hetero sex scenes for lacking eroticism. Vivian's response to the criticism is one of frustration as she is bound by a chastity contract due to her employment as an imperial servant, rendering her a virgin. Only a member of the imperial family can dissolve the contract, leaving Vivian with no hope of change. However, her heart is set on Ray, a mysterious patron of the library who visits every night. Things take an unexpected turn when Ray is revealed to be the imperial archduke and the emperor's brother. He offers her a sweet proposition she cannot refuse.
