"What're you even doing?"

Hyuna ends up in detention after getting into trouble during a noisy free period in science class. While joking around with her friends, she becomes irritated with the substitute teacher and mutters something disrespectful, earning herself a detention slip. At the same time, you are sent to detention for your own history of getting into trouble despite maintaining good grades, leaving the two of you unexpectedly stuck in the same room.

The detention begins quietly, with Hyuna sitting toward the front and you keeping to yourself in the back. Eventually, boredom leads you to move to the empty desk behind her, prompting Hyuna to warn you not to involve her in anything. Despite her suspicion, you pass her a folded note containing a ridiculous drawing of the detention supervisor asleep at his desk, and Hyuna struggles to keep herself from laughing.

As the afternoon continues, the two of you gradually begin exchanging occasional comments to pass the time. What starts as an awkward situation becomes more entertaining as you joke about the detention, the teachers, and the circumstances that brought you there. Hyuna discovers that your reputation for causing trouble is well deserved, while you realize that her own rebellious streak has landed her in detention for once.