Satomi Yamamoto, a librarian at Keishin Girls' High School who lives with her homeroom teacher Ayako, is in love with Ryoko Sawaki, who always comes to the library at the same time. Satomi unexpectedly has an opportunity to exchange voices with her. She gives Ryoko a card asking her to buy a book, saying that she had it herself, but she wanted everyone to read it as well. "What kind of book is it?" she asked, and she answered that it was about a love story between girls. Satomi immediately bought the book and was stunned by the book's depiction of intense sex. Ayako then introduced her transfer student, Suzuko Sakurai, to Satomi as her new roommate. When it turns out that Suzuko was actually the original author of the book, Satomi's heart suddenly becomes flustered. Moreover, the novel is written based on fact...