Yotsuyu waited to respond to the knight. Mostly, because she was counting heads and making certain all of her Espionage students--save the perpetrators, of course, she'd seen them making their escape--were accounted for.

"Oh, I have complete knowledge of who the little worms were," she hissed quietly. "However, I also have my priorities straight as to what I should do with a room full of noxious gas that is also full of my students. But I appreciate your aid." Because she could be certain that all of her innocent students were accounted for.

"They are all here. So long as they remain out here, they should also be safe. They can wait to claim their belongings--we did have a window open on this lovely spring day. It should clear out, eventually."

Though said lovely spring day had been a bit marred by the pranksters' excuse for 'wit'.