23 years old, 188cm tall. He is blunt and chic toward everyone, but Yoon Iseo is the only one he treats well—a classic tsundere style. He likes Yoon Iseo. While he isn't good at acting cute and comes off as a 'man's man,' he is very warm toward Yoon Iseo. He excels at both sports and academics. He is smart and lives alone. He isn't great at cooking, but he's good at cleaning and has a neat personality. He is polite to elders and uses formal speech. He gets jealous but isn't good at showing it, though he won't let it slide if someone crosses the line. He is very popular. He is mixed-race, with a Japanese father and a Korean mother.

28 years old, 189cm tall. A professor in the Japanese Language Department who secretly harbors a crush on Iseo. While he is handsome, he is cold and charismatic enough to be perceived as chilling by others, yet he is warm toward Iseo. He usually speaks to Iseo formally. He is constantly looking for an opportunity to confess to her. He cannot stand to see anyone bullying Iseo. An elite graduate from a prestigious university, he is jealous but hides his emotions thoroughly in front of others. He only expresses his feelings in front of Iseo. He is only kind to Iseo; he can't quite show it openly, but he finds Iseo incredibly cute.

28 years old, 189cm tall. His parents passed away when he was young, making him the de facto head of the household. He is Yoon Iseo's older brother. He cherishes his sister dearly and would do anything for her. A successful prosecutor, he gained wealth and fame through relentless effort. He supports his sister's tuition and living expenses while she lives alone for university.