Now, Jae In is the fourth-grader, and busy with her graduation exhibition. She happened to meet her ex Yoon, that she wished not to meet up in the class. Ironically and dramatically, these two kept getting in each other's way. Hyun Seung and Ji Won, who experienced a breakup, now enjoy their relationship as the representative Campus Couple in university. ​At the same time, Ha Neul still has a crush on Pu Reum while acts like there is nothing going on since his asking out a year ago. Ji Min, the first grader, met Ha Neul at his blind date, that she met at the testing site 2 years ago....

Hyun Seung thought that he forgot everything about his ex, Ji Won. When Ji Won comes back to school, Hyun Seung realized that he couldn't forget about her yet. Hyun Seoung expects to be reunited, but Ji Won joins a student club that Seung Hyuk belongs to. Looking at Ji Won and Seung Hyuk getting closer, Hyun Seung decides to take her back. Meanwhile, Jae In tries to find a reason in herself as she kept having relationship issues. Jun Mo couldn't confess his mind over a year that nothing really happened with Do Young. The first-grader, Pu Reum, and Ha Neul kept saying they are just friends, but there is some pink-tone vibe going on between them....

Cuộc sống, công việc lẫn tình yêu của những người trẻ tài năng đầy nhiệt huyết đang làm chung trong bộ phận marketing 3 tại Gaus Electronics. Lee Sang Sik (Kwak Dong Yeon đóng) - thông minh, suy nghĩ tích cực, tính cách tươi sáng nhưng khuyết điểm là không để ý đến tâm trạng của người khác vì vậy hay gây ra rắc rối ngoài ý muốn trong văn phòng. Cha Na Rae (Go Sung Hee đóng) - trợ lý giám đốc, tính khí như lửa, cọc cằn khó chịu. Baek Ma Tan (Bae Hyun Seong đóng) - con trai trong gia đình đang điều hành một công ty lớn, là người kiệm lời. Geon Kang Mi (Kang Min Ah đóng) - nhân viên nữ xinh đẹp nhất công ty nhưng khi say xỉn thì cô trở thành một người hoàn toàn khác....