Kim Sobin, whom Assistant Seol likes. He's ambitious and wants to gain favor with Professor Song. Cha Chung-hwa as Professor Song Professor of Business Administration at Myongil University, she is an authoritarian. Cold and rational. She doesn't understand Professor Park who wants to get along with students. Believes school is a battlefield of competition not a playground of romance. Eru as Professor Park Professor of Business Administration at Myongil University. A true professor of this era who truly loves students. He dreams of being a Maverick teacher like Keating in Dead Poets Society It is a small dream to eat with students and talk about life candidly. as assistant Seol An assistant in the Department of Business Administration at Myongil University, and a person who is close to her juniors with a sociable style and supports them. She feels sorry for Kim Sobin and tries to help her as she walks alone. Gets angry sometimes at Professor Song because of her savagery but is patient. Yeo Jun's family Na In-woo as Yeo Jun-wan Choi Seung-hoon as young Yeo Jun-wan Yeo Jun's older brother who is in charge of him and the youngest professor at Myeongil University. A genius who understood calculus at the age of 6 and was reading mathematics papers at foreign universities by age 12. He's lived the life his parents wanted without a single mistake. He is an FM personality who doesn't express emotions and is very rational in his decisions, words, and actions. He carries a lot of darkness and unhappiness despite having wealth and honor. He does not feel any meaning in his accomplishments as the youngest person with a doctor title in Korea, youngest full-time professor, etc. as Yeo Myeong-hoon Yeo Jun and Yeo Jun-wan's dad. President of Mijin Foods, a large conglomerate. A successful and elite businessman who came from an ordinary family but joined a large company and climbed his way up to where he is today. He is a competitive workaholic who doesn't take days off. Believes that people who cannot stand out in a satisfactory way hold no value. So Hee-jung as Cha Jung-joo Yeo Jun and Yeo Jun-wan's mom. A musician who graduated with her degree and planned to study abroad but due to family pressure was forced to give up her dream and get married. She carries a lot of complex and intense anger inside. All the friends