Responses
About the teacher, I think it's a translation error. I'm Korean and Japanese is really similar (both the grammar and some phrases) and it think she was actually saying something like "it's got nothing to do with you" as in "it's not because of you/its not your fault." So she wasn't being mean, it's just that yuuya was hurt about it because it's a matter that does involve him as he was left by them.
OH!!! so thats the meaning behind those words!! thanks for covering the misunderstanding and sorry sensei for the mean comment~!(づ￣ ³￣)づ
OK first of all you guys should be more honest with each other or it will get more complicated and worse, And second that teacher doesn't deserve being called that since she teaches and says bad stuff to kids with issues!!! And third you stupid couple should make up in the 4th chapter. ╮(￣▽￣)╭