An accident caused the boss to lose the organic matter covering his terminator eyes, so until he can regrow the stuff, he's forced to hide the situation with sunglasses.
@lurker123 - Ding! Ding! Ding! I think we have a winner. I think Yuki is going to go back to school. The next question will be, girl’s or boy’s uniform.
@MavB_Ver Come on, it's not so big a spoiler that it would warrant spoiler tags.
@ChristineGuinn It'd be more or less impossible to pretend to be of the opposite gender in school, if not illegal, so obviously boys' uniform. The opposite only works in series where it's the most central idea of the whole story, and thus much of the plot would be spent on the unlikely escapades explaining how the crossdressing student is never found out, except for some close friends (or even enemies). I don't think this is quite such a story.