I’m not a fan of the NTR aspect(even though no one was dating) but getting revenge after they kicked him out is hilarious. Literally a case of failing to keep your friends close and your enemies closer. If they kept him around they could easily have used his skill against the demon army. Instead, they made an enemy with a ridiculous ability. He could potentially turn half of the globes population into his subordinates.
Realistically, trying to capture him or kill him on the spot would have been a much more interesting and proper development. A proper leader would have saw the value in the ability but what I do like is that it was addressed that the people in charge did not want the Queen to know they failed. If the Queen knew, their position would have been in question. Selfish and short sighted individuals exist so it’s appropriate at a basic level.