This is my cue.

Canonically the way the House of Bells is said to work is that you are supposed to do everything as a unit even sleep and bathe, my assumption has always been that this has also extended to punishments with the intent that units would subsequently turn upon their weak members (think Full Metal Jacket with the bars of soap) and try to drum them out of the school so their overall result improved.

Her poor exam grades would have kept doing this to her unit as people she thought were her friends started to turn against her. As scary as that was, it paled to...