Seung-mo and So-hee, who usually maintain a good, textbook relationship. However, Seung-mo cannot satisfy So-hee because he lacks bed skills. Concerned Seung-mo consults his friend Hyeon-goo, who has ways of satisfying women, on how to satisfy So-hee. He tells Seung-mo that he has developed a so-called sex recipe. Then one day, Seung-mo has a private meeting with Mi-na using the recipe given to him by Hyeon-goo.