Jungkook is an undercover agent. And an murder case was filed. The murder occurred in an highschool so jungkook was sent to that highschool in disguise

There was a rumour in high school that one girl named Min Yn and Jackson were not in good state so everyone thinks that yn killed him

Jungkook heard the rumour and thought to be friends with yn and know her more

Jungkook saw yn sitting alone in class he walks upto yn and spoke

"Hey why are you sitting alone here?"