The prefect’s bathroom, such as it was, still felt like a step down from the sort of luxuries Gretchen had experienced in her short life but it was certainly a step up from sharing with every other girl in her house. At least an elevation to the prefectship implied that the company she now kept were able to comport themselves adequately well and thus far she had only been obliged to reschedule her ablutions once as a result of the company.

Breezing past Mr Macnair as he came away from the bathroom door Gretchen deduced with satisfaction that one of the girls had claimed the bathroom for their sex. Ostensibly there was an informal rota that the genders stuck to so no one was turned away but in practice they sometimes found the door barred and left irritated: it was never mentioned in prefect meetings but Gretchen appreciated the underlying fact that they were taking part in a silent battle right under the teachers’ noses.

“Thank Merlin,” she said with satisfaction as she closed the door behind her and was immediately met with the scent of sweet soap greeting her on humid air. She blinked away the steam and turned to the bath, immediately stopping in her tracks, frozen to the spot with shock.

“Waterford?” Gretchen blushed bright red, averting her eyes to the floor, brain racing to catch up. “But I just saw Macnair, he couldn’t get in so I thought-”

The magic in this castle never broke, whatever they all said about the staircase; it was simply impossible. But so was the alternative. Gretchen risked another look at the body in the water, the suspicion rising with the steam. She had seen her brother’s shoulders and they certainly hadn’t been that delicately formed, nor the features quite so soft though she had never truly noticed before… “How did you get in?”

There was a chance, however slim, that she was entirely off the mark given how wildly the conclusions she was jumping to deviated from what she knew to be sensible. George Waterford was a boy and to the best of her knowledge people did not spontaneously change sex without warning, and yet George Waterford was also somehow in the prefect’s bathroom when Mr Macnair had been turned away.

And she had been able to get inside.

“It doesn’t make sense,” Gretchen muttered to herself, eyes averted out of propriety but unable to resist glancing at the bath from time to time. Really she ought to leave – either the castle was broken, or Waterford was a girl and neither felt like something she could deal with on her own, but her feet were quite rooted to the floor and what kind of Lestrange backed away from something that might feasibly be used to their advantage?

“I should probably fetch one of the matrons,” she said without the intention of doing any such thing. “Mine is very helpful but yours is French so she’ll probably be less shocked by…whatever is going on.”

Even though Waterford’s reaction told her there was definitely some secret to be teased out and she wasn’t going entirely mad it didn’t give her any clues as to how to force the truth out. Gretchen was gratified to see the reaction she had expected but Waterford was holding his nerve better than she could have possibly imagined.

The silence stretched, the room grew hotter and hotter as embarrassment, tension and steam combined, and just as Gretchen was about to snap out of frustration her eyes landed on the small bundle of clothes.

Her lips curled.

“Why do you have a menses belt?”

If an eyebrow could scream with disbelief then Gretchen’s certainly did as it arched immediately towards her hairline and stayed there. No girl she knew would leave something like that behind and Miss Fawley was far too fastidious to be so stupid – it had been a poor choice of excuse.

“You’re a girl,” she stated simply. It wasn’t a question, though shocked she knew it to be true, and staring into Waterford’s eyes she dared her classmate to lie to her face again.

Triumph shot through Gretchen, her capricious grasp of conscience and compassion failing utterly as she thought of how precious the secret was and that she had sussed it out! She had been right and now…now what? She ought to demand something really. The problem, for Gretchen at least, was that she couldn’t think of anything she wanted and unless she could present everybody with compelling proof she couldn’t guarantee that she would be believed.

There was more at work here than just Waterford lying – surely somebody must know the secret and be keeping it to themselves? Was the family monied? The question of wills was a deadly concern for some families, hers amongst them, so it was a definite possibility.

It struck her for a brief, tantalising moment that there might be freedom in this but the notion quickly ebbed away, like a wave never to return.

“How is it possible that you have kept this a secret?” Her eyes fixed on Waterford’s face, wondering how nobody had ever noticed the softness of her skin, the elegant, uninterrupted curve of her neck.

The words struck a chord with Gretchen. As the orphaned middle child of a less-distinguished middle child she was used to being overlooked, and without the patronage of an influential family member (Kris had uncle Lucius, Tatiana had aunt Mariana and what did she have? Nephele as a guiding hand) she couldn’t see her lot changing unless she changed it herself.

“Blindness and stupidity do tend to go hand in hand.”

Her eyes pierced into Waterford’s face, unsure what she was going to demand, because surely it would be a waste not to demand something to keep her silence? Of course she could bide her time…an unspecified favour somewhere further down the line was surely more valuable than anything Waterford had this very moment?

“I won’t say anything,” she said coolly, the unspoken yet hovering between them. “Lock the door next time.”