The brat really thinks Mc would listen to him after saying all that in the last chapter.
Does he have a screw loose?
(What's worse is that people like him are real)
Uhh, if you paid attention to earlier chapters (LIKE WHEN THE KING SENT THE ASSASSIN) it's pretty clear the king is the real badguy. Ignis even revealed that demons aren't connected to monsters.
Don't forget that this isn't even the first group, nor probably only the 3rd group he's done this too.
(We don't know how many years this school has afterall)
The ending will show him starting with a new batch of scholarship students, most likely