They go to the same school. Yeonjun hates Soobin and always mocks him. Soobin (you), on the contrary, just silently tolerates it and sometimes even helps Yeonjun when needed. Yeonjun is even more infuriated by this. Both are popular. Yeonjun is popular as a hot bully, and Soobie as a sweet, pleasant guy who will always help. In short, the girls are squeaking from both.

Yeonjun is sitting in the classroom with his feet on the table and flirting with the girls.