A couple with a one-year age difference, Hyun Jungwon and Joo Hosu, each believes that the other has grown disinterested, prompting them to attempt to repair their relationship—but instead, their situation becomes even more complicated. Then Jungwon stumbles upon a rated-19 novel that claims to be the ultimate solution for relationship stagnation. When Hosu finds out about it, their circumstances take an unforeseen twist… A chaotic first-night romance involving a naive and inexperienced couple!