I mean.... it was clearly stated that the teacher is new and in no way professional. She's pressured to make the issue "go away" while making an "accomplishment" with no regards to how it's done. Japan police work pretty similarly to some extent AFAIK
Next chapter? That's far too soon... with the current pacing, maybe 1 chapter to win the fight and despair a bit, than another chapter to make sense of what has happened, then only somehow realize a way to keep him alive
Calling it now: they gonna be twins with a connected soul or something like that, diluting the Princess soul further and making MC transition from loyalty to romantic love
On an unrelated note, I hope this manga actually makes them grow up a bit before they meet each other