2020 Final Sex(2021)

Jin-woo sees Seo-yeon and Dong-hyeon together and makes fun of the two. Annoyed with Jin-woo's jokes, Seo-yeon leaves but Dong-hyeon bit Jin-woo's words and misunderstands Seo-yeon's liking for him. Jin-woo starts teasing Dong-hyeon excitedly. Dong-hyeon who is clueless about anything is excited about his relationship with Seo-yeon.