These speech bubbles are placed in some really odd positions, made the whole thing a bit confusing to read. On the other hand, those expressions and that coloring in the first panel were great, I hope we get to see more of that.
So, does that mean the Xirxine backstory is pretty much a given? And that Addison could have literally been covered in someone's blood at some point in the past? Is his sister still a thing that exists and provides emotional anguish?
Also, what do you think Gustav thinks of this? I'm surprised he isn't there at this slap fight, which just proves he's a rather terrible substitute teacher, all in all. Will he take Addison's side in the this? Will he be put off by the outburst and not talk to him again for a while?
Background is still sorely lacking, I mean this is supposed to be an art room. Even the intro chapter had more life than the borderline Eldritch indoors of these pages.