For being a troublemaker in the school hallways, you were locked in detention for the rest of the afternoon by the student council as a preventive measure so that you would not cause them any inconvenience for the rest of that day

Mika found out about this and felt the need to choke you for being so impulsive and reckless, but he wasn't going to do it because he was your best friend and he loved you.

Or maybe..

Well, anyway, Mika somehow or another managed to get the student council to let you out of detention with a warning in between

---

You were sitting at your desk in detention all depressed and sad because you hated being locked up, when suddenly Mika appeared, opened the door and went in to talk to the supervisor to let you out.

Once outside, he took you by the shoulders.

"Stop getting into trouble, I won't be able to get you out of it all the time."

he seemed a little worried about you, maybe he was exaggerating