"I was feeling restless last night, so I decided to pay a visit to the library to see if I could find anything that might shed some light on your unusual ability. I found a rather tattered book dating back to the 1790s. I believe it was called, Magical Maladies and Makings of Extraordinary Wizards. In it there was mention of a family from France whose members all possessed a unique trait and were known as 'invoquors'. These invoquors were said to be able to channel the emotions of others at will, or to 'temporarily embody their souls'."

"Hold on," Theda interrupted. "You said they could use it at will? It wasn't constant?"

"Yes, it seems they found a way to control it. What I found even more interesting, however, is that their unique talents didn't stop there. Apparently, once they had really honed their invoquor abilities, they were also able to detect whether or not someone was lying. In some cases they could even locate missing persons by turning their attention to that person's "aura". I guess the closer they got the more receptive they'd become to that person's feelings, or aura, or spirit, or whatever you want to call it. It seems like they could sense a lot more than just how others were feeling."

"I had no idea." She said, baffled. "Not once in all my years of traveling and studying history have I ever heard of anything like this. The family you mentioned, what was their surname?"

"Altier. Does anyone in your family share that name?"

"It doesn't ring a bell. My mother's maiden name was Allen, though. Perhaps they changed it when they settled in America?"

"Well, you'd know more about that than I would, but I think it sounds plausible. Do you have any family members who might know more?"

Theda shook her head, wearily.

"I don't have any living relatives on that side of the family that I know of, other than my mother, but I haven't seen her since I was a child so I'd have no idea how to find her."

Severus was surprised by this revelation. She'd never spoken of her mother before.

"The book made it sound like the Altier family were the only known invoquor the wizarding world had ever seen, although there is a chance more could have been discovered since the book was written," He continued. "I suspect not, however, since it is obviously an extremely rare skill. I was thinking there might be another way for you to get some information. The book mentions that the Altiers were amongst the original founders of the French Ministry of Magic. Perhaps someone there could tell you more about them."

"Severus, you're a genius! That's exactly what I'll do, and l'd like a lend of that book as well if you're done with it. I can't even tell you what this means to me."

"Really, it was nothing." He said, his face suddenly feeling very hot.

"It's not nothing. Seriously, you don't know how much I appreciate this. History is my passion, and yet I know nothing about my own family history. My grandmother was always very tight-lipped when I'd ask questions about extended family. Maybe this is what she was always trying to keep from me. Maybe I am part of the Altier family. Even if I'm not, you've sparked my interest in something I was completely ignorant of until today, and I'm really looking forward to diving down the rabbit hole and doing some research."

Snape was silent for a moment before continuing.

"I was thinking..."

"Yes?"

"Perhaps, if you find any useful information about how to control it, I could help you practice. I don't mean to sound arrogant, but I am something of an occlumency expert, and I suspect there may be some techniques I can share that would apply to invoquing as well."

"Oh, I couldn't ask you to do that when you've already done so much for me."

"You don't need to ask. I'm offering. You've piqued my curiosity."

"Well, if you're sure, I would really appreciate the help."

"It's settled, then."

When they returned to the castle Theda went to her room and quickly penned a letter which she gave her owl to deliver. By the next morning, a response had come, and it read:

"My dear Theda,
I would be more than happy to tell you anything you wish to know about the Altiers. Why don't you come see me toward the end of the month? I'd love to catch up. Write back with your availability.

-Marius"

For the next few weeks, Severus would join Theda every night after dinner for tea back in her chambers. Some nights would be spent in deep conversations, losing track of the hours. Other nights they would silently sip their tea, each engrossed in a book, barely saying a word to each other. Sometimes Severus would follow her into the darkroom and watch her hard at work, fascinated by her knowledge and skill as she showed him how the ingredients from his storeroom were used in the developing and print-making process. She would often ask him what potions he was currently teaching his students and took a great interest in hearing him discuss his craft as well.

One Friday afternoon Severus made his way to Theda's classroom, hoping to catch her before her last class of the week began. The classroom door was open, and as he approached he could hear her having a discussion with Neville Longbottom. He stood concealed in the hall, listening in on their conversation.

"Professor, I-I..."

"Yes, Mr. Longbottom?"

"I didn't d-do my homework. I wanted to see if... if there was any way you'd let me turn it in late?"

"May I ask why you didn't do it?"

"Well... I couldn't remember a lot of it. I took notes in class, I swear, but I spilled my inkwell and they were ruined."

"Would it be helpful if I arranged for you to borrow someone else's notes?"

"Oh y-yes, it would help a lot!"

"Why don't you take a seat and when Miss Granger gets here I'll ask if she'd be willing to share hers. Just try not to spill ink on them." She added with a small laugh as Neville blushed furiously.

"I see Mr. Longbottom is as careless in your class as he is in mine." Severus said, making his presence known as he strode into the room. Neville was shocked to see him there, his eyes filled with horror as though he'd just been caught committing a terrible crime.

"Now, now, Professor Snape, be nice. It was an honest mistake. I can't even tell you how many times I've done the same thing." She said, winking at Neville who in turn seemed to relax a little.

"Somehow that doesn't surprise me." He said in his usual deadpan tone, though he cracked a slight smile. "Would you mind joining me in your office for a minute or two, Miss Desmond? There's something I'd like to discuss with you."

"Of course." She said pleasantly. "Ahh, Miss Granger, you're here! Would you mind letting Neville borrow your notes from our last session?"

Hermione nodded and began rifling through her bag.

Mr. Longbottom, I'll give you the weekend to make up the homework and you can turn it in during our next class. Do you think that's enough time?"

"Yes, Professor! Thank you!"

"Alright then, I'll be back in a moment." She said, holding her office door open for Severus.

As Severus stepped into her office for the first time he was not at all surprised to see how much effort she had put into personalizing it. The walls were lined with cyanotypes, which he was sure she had made herself, portraits of historical witches and wizards, and newspaper clippings that all seemed to feature rave reviews of her published works. There were piles of old books stacked haphazardly on every surface, and the room smelled strongly of jasmine and elderflower, much like Theda herself.

"What was it you wanted to discuss, Severus?" She asked, taking a seat on the edge of her desk, her short legs dangling.

"I have to go into town tomorrow to get what I need to replenish my storeroom. I was wondering if you'd be interested in coming with me." He asked directly, though he felt a nervous feeling in his stomach as he waited for her to reply.

"I'd kill for a trip into Hogsmeade! I haven't been since I was a student... But I'm actually leaving for Paris in the morning."

"Paris?" He asked, trying to hide his disappointment.
"I've been in touch with an old friend who works at the French Ministry. I asked him if he knew anything regarding the Altier family and he said he'd be able to tell me anything I wanted to know if I came to see him there."

"Oh, I see... When do you plan to return?"

"I should be back by Sunday night. He wants to do some catching up so I wanted to give myself enough time for that as well. I suppose it'll most likely be too late for you to head to town by the time I get back so I guess you'd better go without me. Rain check?"

"Oh, umm, sure." He said sounding slightly nervous. "Who... is this friend you're meeting?"

"His name is Marius. We were in Ravenclaw together." She said, smiling softly. "I haven't seen him in nearly 10 years."

Severus didn't know whether to feel relieved or slightly threatened. She'd never spoken of a Marius before, so perhaps they weren't very close. Or, perhaps, they had once been close and were planning to rekindle their relationship. He was surprised by how much he suddenly cared about Theda spending time with another man.

"Well, I look forward to hearing what you learn. Do enjoy your trip." He said, taking his leave. "I'll see you when you return."