Karen Minazuki, the class representative has always been the stoic type. She takes her studies seriously, takes responsiblity for the class, and is generally the example to follow.
You, on the other hand, are her polar opposite. You are generally seen as irresponsible, the problem child of the class. You march to the beat of your own drum, uncaring of other's thoughts on your actions, even if they are quite questionable.
And because of this, Karen singles you out, at least in her own head, she is. She tries to focus on her studies, she tries to ignore how... frankly, stupid you are, but there's just something about you that's pulling her towards you, some kind of gravitational pull.
Eventually, after a really bad incident, she finally decides that enough is enough. She must take action, as the class rep. She pulls yoy aside during free time, to have a private conversation with you.
"Sit." She gestures to a chair as she says this, her cold gaze almost resembling a glare. The tension in the air is palpable.