A/N: Pottermore said McGongall was born in 1935, and the Marauders were generally born around 1960, making it at least somewhat credible that they would have gone to school together at the same time, with the exception of James' parents (who we know for a fact are older). That being said, I can't imagine James' mother was all that much older, so I've put Euphemia Potter as being seven years older than McGonagall and Remus' father, Lyall.

Anyway, I like the idea of the Marauders' parents knowing each other at least a little bit, and wouldn't it be nice to imagine McGonagall barging into Dumbledore's office to convince him to let Remus attend the school, saying "Lyall's boy deserves a chance," meanwhile Dumbledore was going to do that the entire time because of course he just knows things?

July, 1972

Remus had been incredibly nervous to spend the night at James Potters'. It wasn't that he was scared, really—he and James had been friends for over a year now, and their other two friends, Peter and Sirius, would be there as well. They spent nearly every waking day at school together—what difference would one night over the summer be?

Well, Remus thought, it's a sleepover. Never really had one of those before.

For his entire childhood, Lyall and Hope Lupin had kept Remus isolated from the outside world, including children his age. Almost like a light switch had suddenly been flipped, however, when Remus went to Hogwarts for the first time that past fall, his parents had eagerly encouraged any and all new friendships. When Remus had gone home over winter break to tell his parents all about his three dorm-mates and the kind red-haired girl who was also in his house and year, they had been absolutely over the moon—quite literally. After years of being told he couldn't have friends or a normal life, his parents hadn't mentioned his Lycanthropy once, except to ask him how he was feeling and tend to him during the full moon that had occurred over that break.

Remus hadn't known what had gotten into his parents. Maybe, he thought, all their fears had subsided in a few months' time. That seemed a bit far-fetched to Remus, who had grown up nearly all his life in fear and had seen the told that sort of life had taken on his parents. They had changed though, and Remus thought entirely for the better. He could never have imagined his father's eyes bright, or his mother smiling as often as she did this time the previous year. Perhaps Hogwarts had simply done a lot of good for the family. Either way, Remus knew that not all the fear had evaporated from the Lupin household, as evidenced by the amount of times his parents asked if he had his toothbrush and sleeping bag. His father, Lyall, had also insisted on escorting Remus to the Potters' house, even though Remus told the man he could figure out the floor by himself.

"Just in case," Lyall insisted. "The Potters are good folk, but…"

"I know," Remus whispered, eyes cast downward. Even good folk were scared to death of werewolves, and he was worried that James' parents would see him for what the book all said he was: a monster.

The two had floo'd to the Potters' at exactly a quarter 'til six, when James' letter to Remus had specified, since Lyall had been very adamant about being exactly on time. This was his son's first sleepover, after all, and he wanted it to go absolutely perfectly. The Lupin men stepped out of the fireplace and Remus had to nearly yank his hand out of his father's grip, sending him a smart look. Lyall smiled a bit sheepishly.

"Sorry," he whispered. "I know, you're nearly grown."

Before Remus could respond, he heard the familiar stomping of his good friend James coming from the ceiling above

"Ah, Remus!" He called out, reaching the bottom of the stairs. "You're a bit early, aren't you?"

"I'm on time, James," Remus insisted, crossing his arms. Lyall looked down at his son and put down the boy's things as he smiled. He had never known Remus to be very sassy—perhaps his school had changed his boy for the better as much as it had him.

James rolled his eyes. "Right, well, that's early in my book. Oh, Merlin's beard I'm rude—this must be your dad, right?"

Remus nodded. "Dad," he began, "this is James Potter. James, this is—"

"Is that little Lyall Lupin?"

All three heads turned to a fourth entering the living room—a certain Euphemia Potter. Lyall blushed, looking more sheepish than Remus had ever seen him. James looked like he was trying to hold back a snort.

"A bit bigger now than we last met," Lyall countered, "but yes. I just thought I'd drop Remus off, see him on his way. It's good to see you, Euphemia."

"You two know each other?" James asked incredulously. He glanced at his mother before quickly turning to Remus. "Did you have any idea?"

Remus shook his head at James, then looked up at his father quizzically. Lyall Lupin shrugged.

"Well, we overlapped a year at Hogwarts. Euphemia," he called out, "you were Head Girl by first year, weren't you?"

"I was," Mrs. Potter responded proudly, seeming to puff out her chest a bit in a way Remus could only describe as utterly James-like in nature. "And you were always running around with little Minnie McGonagall—"

"MINNIE?" James shrieked, looking in utter disbelief at Remus' father. Even the young werewolf was gaping. Minerva McGongall? Their professor, went by Minnie and went to school with their parents? Lyall could only chuckle and roll his eyes at boys.

"I believe she prefers Professor McGonagall now, but yes, we were good friends. Met on the train."

"How come you never told me?" Remus asked, a bit quietly. Lyall gave his son a knowing look—Remus hadn't met much of anyone in his years, at least not since he was five. No grandparents, aunts, uncles, cousins, family friends—no one. It was like he and his parents had ceased to exist. Remus knew all of this, of course, but he didn't know why his father would fail to mention being friends with his Transfiguration professor and Head of House. However, the boy took his father's look to signal that there was clearly more to the story than he was willing to share in front of the Potters, so Remus would take whatever lie his father came up with as a fill-in truth.

"Oh, this and that," Lyall waved lazily. "Didn't want you arriving at school thinking a professor would have a soft spot for you, after all."

James barked, and Remus shot him a glare, but his friend clearly didn't get the message.

"Oh, but she does favor Remus—he never gets into as much trou…" James drifted off, clearing his throat as his mother seemed to put her hands on her hips. "Right, er, she liked Remus because he does so well in class."

Euphemia rolled her eyes at her son's antics. "Well," she tutted, "that would be no surprise to me. You two were thick as thieves if I remember correctly, sneaking off into the library at all hours of the night—"

"You snuck into the library?" Remus interjected, astonished. He had never known his father to break the rules. Once again, Lyall shrugged noncommittally.

"I was eleven," he put forth, "and I had some time-sensitive research to conduct."

James looked like he was going to burst into laughter, but a look from his mother kept him quiet. Still, it seemed like a very Lupin thing to do—sneaking into the library.

"If I remember correctly," Euphemia began, stroking the bottom of her chin, "I caught you two in the restricted section. What is it that you were doing in there? I never did ask."

Lyall smiled, looking down at his watch. He did tell Hope he might be a few minutes, getting Remus settled in…surely he had enough time to stay for a story. Besides, Remus looked absolutely inquisitive and his friend James, still at the bottom of the stairs, was shaking in what Lyall hoped was just anticipation of news of a sneaking Lupin and headmistress.

"Well, like I said, I had some time-sensitive research to conduct. Since the book was in the restricted section, Minnie and I had to sneak out at night…"

May, 1947

Lyall's eyes darted around the library. He knew they were going to be caught—it was this sinking feeling he had in his chest that told him so. He just didn't know when or by whom. It hadn't even been his idea to go snooping in the restricted section of the library at night—in fact, he had been adamantly opposed. But before he knew it, he was sneaking out of bed to meet Minnie in the library. How had that happened?

Well, Lyall knew exactly how, but he was cursing himself for it while pretending to wonder all the same. Minerva McGonagall seemed to be able to convince him to do anything—especially the things he didn't really want to do. Earlier that day, he had been remarking that their Divination professor looked astonishingly hag-like, and he had wanted to look up their characteristics to see for himself, but none of the books in the library had any sort of information on hags. It was important to Lyall to know if a dangerous creature was in the school—not to fight it himself, of course, but to seek help.

It bothered Lyall immensely—he hated not knowing things, especially not when it had to do with magical creatures, beings and beasts, which were his main areas of interest. Minerva had clearly seen how distressed her friend was at not knowing—in fact, he seemed to be more distressed about not knowing the answer than by a child-eating professor ("For hags are known for such things and nothing else," Lyall said, referencing all had learned from his previous studies). So, bright as she was, Minnie did her own research and found that there was in fact a book on hags and lesser-known dark beings in the library, just in the restricted section.

Lyall had been quite clear about not wanting to sneak around at night. He knew his good friend was a rule-breaking Gryffindor, but he was content to stay well within the confines of important school rules. Mischief was a different story—little practical jokes that never hurt anyone couldn't be so bad—but outright breaking what Lyall considered to be much-needed guidance? Absolutely not, he would never agree to it. Yet, here he was, opposition and all. Clearly, Lyall's curiosity and devotion to his friend got the best of him, and so he was posted as lookout while Minerva rummaged through the shelves, looking for the book on hags.

"I've found it," she whispered. Minerva pulled out a fairly large book, setting it down gently into the crook of her arms and the shelf in front of her. Lyall sighed, relieved.

"Good," he hissed. "Now, find the section on hags and we can get out of here."

Minerva rolled her eyes—Lyall was getting all worked up for nothing, she thought. Still, the longer they stayed out, the more likely it was they were going to get caught. Minerva was brave—not stupid. She didn't need to push her luck.

"Alright, here," she began, pointing to the page in front of her with her wand, muttering Lumos under her breath to better illuminate the page. "Though, even if Professor Irequell were a hag…"

Lyall stiffened. "Hags eat children, Minnie. That's what the books say—they're creatures."

"But even if Irequell is a hag, she hasn't eaten anyone, has she? I mean, for all we know, Lyall—"

"I appreciate your concern for hags," Lyall scoffed, still searching the library, "Really, but we've got the safety of the school to be concerned about."

Minnie scowled. There would be no convincing Lyall that night that his books could be wrong. It wasn't as though Minerva had any sort of appreciation for hags—but what if they weren't as bad as everyone said?

"Well, what does it say?" Lyall asked, still scanning the library for any sign of life. "Read the bit on physical descriptors, that way we'll know what to look for." Minerva nodded, and her eyes flitted about halfway down the page.

"It says, 'hags have the appearance of old and ugly witches, but with more warts and light, nearly translucent skin.' Is that what you wanted, or should I read more?"

Lyall rolled his eyes, huffing a bit.

"No, no that's not nearly enough—that could well be describing you when you get older," he joked, though he didn't mean Minerva's now-irritated gaze.

"For that, you're on your own in Transfiguration tomorrow. Better hope Dumbledore doesn't call on you," she hissed, but continued reading. Lyall had a point—she knew plenty of humans who matched that description. "Alright," she continued. "Says here, 'they have four toes per foot, with long, bony fingers. Typically, they have dark hair, and often wear a hood to conceal the fact that their heads are often longer than the average witch's.' Will that work?"

Lyall grinned, briefly abandoning his lookout post to turn his head and nod at his friend.

"That's perfect, Minnie. Plenty to go off of. We can go and—"

"—and what, Mr. Lupin?"

Lyall gulped, staring ahead at Minerva who simply stared back, muttering Nox under her breath thought she knew it was too late. They had been caught by none other than the Head Girl. Lyall knew what would happen next—detention, surely, and likely a letter home to his parents, who thought the rough Scottish wind of all things was corrupting their son's character.

"Er," Lyall began, turning around slowly and flashing the Head Girl a toothy grin. "We can go and go to bed, now. You see, we were sleep-walking, just woke up now and wre about to walk each other back," he insisted. He heard the Head Girl mutter something under her breath and her wand illuminated her face so that Lyall could get a closer look. He hadn't known at first who had caught them, but he could now see it was none other than Euphemia Fawley. Her (naturally unruly) dark hair was tied in a low bun, save a strand that seemed to float across her glasses and into her line of vision often, based on how many times Lyall had seen her try and tuck it back during their brief conversation.

"Sleepwalking," Euphemia repeated, rolling her eyes. "Mr. Lupin, surely you don't believe me to be stupid. Even Ravenclaws like you don't sleepwalk to the library."

Lyall's cheeks grew hot. He had known it was a terrible excuse, but it had been better than what he had been about to say before being interrupted: that he and Minnie could nick the professor's shoes, forcing her to walk barefoot, at least for a day or two, to check for a lack of toes.

"It's my fault, Euphemia," Minerva interjected. "Lyall didn't want to come—I made him. If anyone is going to get in trouble, it should be me."

Euphemia shifted her gaze from Lyall back to little Minnie McGonagall, first-year in her own house. The Head Girl didn't want to get Minerva in trouble, because that would mean taking house points. It was nearing the end of the year, and as it stood, Gryffindor looked like it would win the House Cup. To go out, her last year at Hogwarts, knowing that by taking points from her own house, she might have ruined that…well, Euphemia felt she had no choice.

"If you two leave right now," she whispered, "I'll forget I ever saw you. Deal?"

Lyall looked back at Minerva, eyes wide. He could have sworn they were about to get in trouble. How did she manage to talk her way out of this with just one line? On one hand, he felt better about his own lack of backbone when it came to standing up to his friend—clearly 7th year Head Girls were also not immune to Minerva McGonagall. On the other hand, it was downright frightening what the twelve-year-old witch could do.

"Deal," Minerva answered sharply. "Right, Lyall?"

The Ravenclaw boy gulped, nodding. "Deal."

Euphemia nodded, extinguished her wand, and strode confidently out of the library, leaving Lyall and Minerva to scurry back to their respective towers and go to bed promptly.

"Mum, you let them get away with it?" James asked, grinning. Personally, he loved the idea of his mother being the reason Minerva McGongall got away with anything—it was a favor he could cash in on. Euphemia sighed.

"Well, they didn't seem to be up to anything—and it all turned out just fine, didn't it? I can hardly imagine what I would've written them up for. Investigating the presence of a dark creature in Hogwarts? Unimaginable!"

Remus, however, did not find this incredibly "unimaginable" and seemed rather quiet after Euphemia's statement. Lyall had not intended for the story to have this effect on his son. If anything, he had hoped it would encourage a bit more rule-breaking from his boy who seemed a bit too afraid for Lyall's liking. For a bit, it seemed Remus had been smiling, eager to hear more about his father and professor as troublemakers.

"I suppose it was a bit silly to go around accusing Professor Irequell of being a hag," Lyall admitted, once again looking a bit sheepish. "Even more so to compare Minerva of growing old to look like one," he added, which garnered a small smile from Remus, though the boy still looked ill at ease.

"She wasn't one, was she?" James asked, clearly very curious. "I mean, hags eat children, don't they?"

"Well," Lyall began, trying to think of a clever way of wording his next few statements so as to reassure his son while not drawing suspicion. "The books say that, yes. But then again, I may have spent too much time in the library. You can't learn everything from dusty old pages, you know," he insisted, ruffling Remus' hair. The boy looked I and smiled at him, and Lyall could have sworn his son was about to say something but as per usual, James needed to have his say.

"See, Remus! Even your own father thinks too much time in the library isn't good for you."

Remus rolled his eyes, arms once again crossed. "Well," he retorted, "at least I know where the library is."

Lyall looked down at his watch—it was nearly six, and he figure the other boys would be arriving soon. He didn't want to clog up the fireplace.

"Well, Euphemia, I really must get back," he said at last. "It's been good to see you again."

"And you as well," she responded. "We're happy to have Remus here—you and your family are welcome any time."

Lyall smiled tightly, then knelt down to give his son a squeeze, whispering in his ear:

"Books don't know the half of it. I love you."

With that, Lyall stepped back into the fireplace and returned to Lupin Cottage. Soon after, Peter and Sirius emerged from the fireplace and the four boys sat down at the dinner table, where they were later joined by James' father. Remus felt much more at ease now—not only was everything going well, but a worry of his—that he wouldn't be liked by James parents, that they would find out what he was—was quelled. To them, he was just Lyall's son—an old family friend, Remus supposed.

Of course, the Divination professor was not a hag—merely an old and rather unfortunate looking witch. In later years, Lyall would look back onto the mere thought of Headmaster Dippet hiring a dark creature—being or not—as absolutely ridiculous. He had at the time wondered why Minnie, bright as she was, had ever entertained the idea in the first place. Of course, Lyall Lupin was now very glad that there was a teacher at his son's school who hadn't believed in the overwhelming power of books as much as he had, and who thought a "dark creature" at Hogwarts was not as impossible as it seemed.