A Reasonable Arrangement
Marietta contained her freakout to the span of three seconds, and when the knock came again, she was perfectly still. She would not react, no matter what. Already having cast a locking charm on the door, she would cast it again if she heard the unlocking charm, and sooner or later whoever was trying to get in would give it up completely.
"Excuse me, I need to use the broom closet." She might have recognized the voice if she thought about it, but it well and truly did not matter who was on the other side. "There's a painfully cute girl over here, and she doesn't want to be seen by anyone else." Her eyes could not be rolling more painfully. She wanted to tell the wizard on the other side that perhaps if she did not want to be seen, she could just not be getting up to that sort of thing. That seemed to be the ideal solution to the problem, after all.
The matter was made worse by the fact that she actually had a legitimate reason for being in the broom closet, she had something that she had every right to keep secret, but it gave her an idea. He could not see her grabbing her breast, after all.
"I can't come out because I'm cursed," she explained. Instead of grabbing any part of her body, however, her hand went to the doorknob. She tried to pry it off with her other hand, but somehow it was stronger. "Please, don't look at me," she begged, trying to keep the door locked with her wand.
"I might be able to help you in some way," the wizard said. "Can you tell me what led to being cursed?"
"No, no, it's quite all right, I just need to be left alone. The horrible witch who put this on me is going to remove it if I explain how bad it is. She'll realize it's too much for anyone to bear," Marietta explained. "She will most likely be ashamed she would ever do this to another witch."
"Okay, well if you're sure... I could go get her for you."
"Thank you, it's Hermione Granger. I'm sure you've come across her once or twice. She certainly makes herself known to young wizards."
There was no reply, so she assumed he had already walked off. Whether or not he found her, at least he was away, so she allowed herself to relax a bit. Fortunately her hand was returned to her control. Peeking through the crack in the door to check that there was indeed no one on the other side, she breathed a sigh of relief. She was still naked, but at least she was alone.
"I cannot risk telling anyone. I should have known the curse would have some way of making it worse, even when I am behind a door." Despite her hatred for it, she found herself more and more interested in how the logic of it worked, but questions regarding that could wait until after Granger removed it.
Eventually another knock came.
"Granger?" she asked. Her clothes returned immediately as the door opened. "How is that a random time interval?" she asked.
"What are you going in this closet?" the witch asked. It seemed Cho had already found her.
"You know why I was in there- I was naked up until a moment ago."
"Oh, well, that was lucky. I didn't want to see you naked."
"I should hope not. The best thing to do would be to remove the curse from me."
"Are you sure we should, Hermione?" her friend asked. "Has anyone even seen her yet?"
"How dare you! Of course someone has seen me. You know Davies; he's on the Quidditch team with you-"
"The Quidditch team Umbridge disbanded," Cho said, rolling her eyes. "I haven't seen any of my teammates in a while, Marietta. I'll ask him if he saw you naked. He might lie about it, though. What's something I could ask him to make sure?"
"Why would he lie about seeing me naked in Transfiguration? No one would ever believe him?"
"Yes, no one including us," Granger said. "You expect us to believe you were naked in class and no one else noticed?"
"I was in the back of the room."
"Surely Professor McGonagall-"
"I had my schoolbag on the desk in front of me- I also was not wearing my cloak at the time, so it did not disappear with the rest of my clothes. Davies saw me before I managed to get my cloak on. Are you happy now?"
The two witches on the outside of the broom closet exchanged a look.
"We've decided we've been really awful to you, but until we can be sure Davies saw you, the most we can do is lessen the curse," Cho decided. "From now on, one article of your clothing will disappear at random, instead of all of it at once."
"Don't worry; your underthings will not reappear on top of your uniform," Granger added.
Marietta wanted to protest, to say that she was still being treated unfairly, but she had an opportunity. All she had to do was prove that Davies had seen her, and then they would remove the curse entirely. She could get their whole little club thrown out of school as soon as she had the use of her tongue again.
"How can I prove that I was seen naked?" she asked. "What kind of proof would you accept?"
"Well, an Unbreakable Vow would be tricky," her friend said. "Most people would not agree to one, even under the best of circumstances. I guess you could have him tell us what your body looked like."
She thought about it. There was no way it could be as embarrassing as being seen naked in the first place.
"That would require witnesses, though," Granger said. "It's not just the two of us that need to be satisfied with the punishment; it's the whole Defense Association."
"I can't have him describe my body to everyone-"
"Well, you would have to describe it to us, first," Cho said. "That way we would know if he got it right."
"You have already seen me naked."
"Well, I have, but no one else has. Could you tell Hermione what your breasts look like, so no one would suspect that I was just confirming whatever Roger said?"
"I don't know that he saw my-"
"Be as detailed as possible."
"Well..." The two witches were staring at her. She did not like the idea of describing her body, even when it was just other witches. "They're... normal, decent looking breasts, not that I take pride in that sort of thing."
"That's not very specific. How big are they?" Granger asked.
"They're... well, they're certainly not massive-"
"I don't know, they seemed pretty sizeable to me, when I saw them yesterday. I would say they're cute, though," Cho said.
"Sizeable and yet cute? I'm not sure I understand-" Marietta's clothes disappeared again. "Oh, that's what you mean," she commented, having a look before the mortified witch could cover herself. "I didn't know you had freckles all the way down to your chest."
"Well, you wouldn't know if you hadn't cursed me-" she started, suddenly finding that her tongue was hanging out like that of a panting dog. Eventually the vulgar expression subsided. "What even was that? I thought that I was just going to grab myself-"
"No, it's whatever makes it worse at that given moment," Granger explained. "If you were in Professor Snape's office, you would probably start sucking on a potion vial." She looked over at the other witch, who nodded. "It's a very complicated curse."
"Well, can you at least give me the less severe version in the meantime?" she asked.
"Of course. We've been awful to you, after all."
"Simply ghastly. You did nothing to deserve this kind of treatment."
As soon as they waved and left, Marietta swore. She should have known they would be beholden to the rest of the group- it was a joint decision that there would be a substantial punishment, after all. Apparently Granger had something milder planned. Of course, that was her definition of mild, meaning it could have been something extreme, like being made to apologize in front of the entire school- or to make matters worse, the deposed Headmaster Dumbledore.
Perhaps she could stand to be grateful the punishment had lessened, but at this point she had only two things on her mind. Firstly, she needed to get Davies to be able to describe her nude form, and then she wanted revenge. It was their fault in the first place for defying the High Inquisitor, and for that they had yet to pay a suitable price.
It would not be enough to simply visit the same punishment on one of them. No, they had all committed the same crime, and they had all made themselves responsible for punishing her unjustly, so she would punish them all with the same punishment, at the very least. If she trapped them all in the same place and cursed them all at once, the wizards would probably take advantage of the witches, and then they would all be expelled, so much the better for the academic standard of the school. She highly doubted any of them had been paying attention in Defense Against the Dark Arts, meaning they would all be abysmal in the way of theory.
One thing they definitely would not understand is that if a witch wanted to defend herself, she would do best to strike first.
Marietta went to the library and poured over several books on curses. She could not find anything that specifically related to clothes disappearing, which she expected, so she looked for something with a narrower scope. There had to be a curse that could adjust itself based on the situation. Unfortunately, she knew not where to look to find more information on it.
It was worth considering that asking about the curse might be as bad as talking about it, since if she were clever enough she could lead adults into figuring out what had happened to her, but thus far only some of her underthings had disappeared. There were limits to how bad the effects of asking a question could be. As soon as she walked over to the librarian's desk, however, she noticed her pants were gone. Flattening her skirt, she realized she did not know whether that was a random effect or the consequence of approaching a faculty member for help.
To her surprise, her skirt disappeared as well.
She flattened herself against the librarian's desk, keeping her schoolbag to her back, in hopes that no one would notice, else see anything if they did. Her face was red and Madam Pince noticed.
"Excuse me, Miss Edgecombe?"
"Yes, would there happen to be any books on curses? Complex curses that make themselves worse on context?" she clarified. It was almost certain that her skirt disappeared because she was going for help, but she was already there. Looking around, it appeared some people had noticed her pressing against the desk, but no one had said anything. Fortunately her schoolbag was covering most of the bare skin to be seen, though in the best of circumstances people would think she had picked today to wear a particularly short skirt.
"I believe you will need a permission slip to access the Restricted Section, where books on such curses can be found. Not two days ago there was another student your age who told me she was returning a book to that section, and it had been most useful in-"
"Yes, that would be the book. Might you remember the title?" she asked. She looked around again. It would probably seem bizarre for her to be so close to the librarian's desk, and as she expected, Potter was sitting there smirking. "Also, could you tell me any book on how I might get my quim stuffed?"