Basically, Mystia and Rumia didn't do anything but they still got hit. Poor them.
Redddddddddddd!!Pantiiiiiiies!!Her bottommmmmmm!Waaaaaagh!Crush...Knave of the FirefliesHotaru no Baka.
Hotaru no Haka: Grave of the Fireflies...Yes, Ma'am.The first thing I'll teach you is......no horseplay in the classroom.