Naruse Soushi, a 38-year-old (male) private secretary to a politician has been reincarnated in another world...into the body of the captured princess knight Reina. And through her devoted efforts, she has been strengthening her position as the yuri prostitute Lillion-while still a middle-aged man on the inside. While undergoing a trial to be promoted to a high-class prostitute, Lilly makes contact with the memories of Reina, the original owner of her body, and learns about the promise she made at dawn with the Lady of the Moon!