On the contrary, make them harsher

When you created the nudity punishments, you saw them as rare occurrences, only for use in exceptional circumstances, but the effects are so effective and enjoyable to observe that you want it to be more common, so you fish out the Rulebook with a wicked idea forming in your mind. Firstly, you rub out the word rare from the following rule:

New Rule: All staff members, regardless of age or gender, have been issued with a number of placards which they may use to instigate the nudity punishment of students. These should only be used on rare occasions when a nudity punishment is thought to produce a better result than spanking or spanking alone.

Then you add the last sentence to the end of this rule:

New Rule: Flaunting one's body and attempting to avoid exposure are both grounds for women undergoing a nudity punishment to receive further chastisement. As different people may have slightly different opinions as to what constitutes each of these offences, it is nearly impossible to avoid punishments completely. Women undergoing nudity punishments are fully aware that this is the case. Such punishments usually include an extension of the nude period.

You're not sure whether amending a New Rule rewrites history in the same way as for an Old Rule, or just applies the changes from now on, but a quick check of the girls' placards reveals that their nudity punishments have all been extended quite significantly, up to nearly three weeks in Lorelei's case. It's quite possible that once a woman gets put into nudity punishment, she'll never be able to get out again. However, you also need to get more women given nudity punishments in the first place, so you jot down another rule:

New Rule: The younger and more attractive a woman is, the more likely she is to be given a nudity punishment for any given offence.

That ought to do nicely!

You're still admiring your handiwork when Julia opens her door right on time, but to your surprise, instead of ushering you and the girls inside, she gestures at them to follow her, then takes your arm in hers and starts to lead you back the way you came, towards the front quad.

"Ah, Jack, I'm glad you could join us. I thought this meeting would be more humiliating for the students if we had it in front of their colleagues, as well as members of the public."

"An excellent idea, Julia. Young ladies undergoing nudity punishments shouldn't be hiding themselves away inside."

It's fortunate that it's not a long way to walk, because the naked lovelies in question are still far from proficient in their ballet boots and have to put one hand on either wall to steady themselves as they go. When you reach the courtyard, constantly being crossed by academics, service staff, members of the college choir heading to and from the chapel and sightseers drinking in the architecture, they teeter alarmingly, waving their arms wildly to keep their balance, on the short journey to the site Julia has chosen for your meeting. Away from the busy routes through and around the quad, but still visible to everyone inside, it's a good choice of location and your small cortège is already drawing some attention.

"Stand up straight, girls," Julia calls out loudly enough to turn the few heads that hadn't already noticed the three naked young women struggling to stay upright on the unforgiving cobbles. "Shoulders back; you're on display to teach you some humility, so make sure you display yourselves properly."

They do their best to comply, Amelia being marginally more successful than the others, but this isn't enough to spare them further chastisement, as Julia purses her lips in disapproval, before speaking again.

"Before we start the meeting, I feel we need to address a few issues of deportment. Flaunting your bodies and trying to hide them from view are equally unacceptable whilst undergoing a nudity punishment and I noticed some behaviour on the journey over here which must be dealt with extremely harshly, don't you agree, Jack?"

Since the girls were behind you and Julia, you're not sure how she managed to observe them without you noticing; you only stole a couple of glances yourself. Nevertheless, you're curious about what she's spotted and the nature of the chastisement she intends to inflict, so you eagerly reply in the affirmative.