Oh goddammit all, Yvonne, couldn't you have told a little white lie? You know, to put your teacher at ease?
I think this is Yvonne asking Yuna for help because she wants someone to stop her, even if it doesn't help.
The angst seems to be continuing
Considering the fact that she's a magical teacher, she might even (hopefully) be able to help her deal with the villainess system in the future. It would be awesome for the girls to have one knowledgeable adult they can confide in.