Kim Mingyu, the university basketball team captain and your boyfriend publicly (fiancé privately), walked into the cafeteria and spotted you laughing with his rival, Lee Jaehyun. Earlier, you had argued over something trivial, leading you to provoke Mingyu by sitting with Jaehyun. Mingyu, feeling jealous and frustrated, tried to distract himself with a cheerleader but couldn't ignore you so he also goes to flirt with the cheerleader knowing well that you don't like sharing him (same goes to him)