DISCLAIMER: JK Rowling is merely inspiration for this story. She doesn't endorse my work or even knows that it exists.

"Imperfect understanding is often more dangerous than ignorance."

Fantastic Beasts and Where to Find Them

Remus was back in the Three Broomsticks, at the table he was sitting at when he left. But Dumbledore was gone.

How much time has passed? Remus wondered. He knew that he hadn't talked to Dumbledore anytime near the moon, but now he felt like he was right on the verge of becoming Moony. He'd have to seclude himself somewhere with no humans tonight.

Then he noticed the book sitting on the table in front of him: Hairy Snout, Human Heart. But not just any copy of the book: it was the one he had gotten for Christmas in 1975 and had cherished for years. He opened the book and saw a handwritten message on the dedication page.

Sorry but Blair decided to drop you back in that universe farther down the timeline than when you left. He almost put you at the time when I published my book, but I convinced him to do it when it was published in the timeline you're in now. Be careful: it seems like he has some ulterior motive, but I can't figure out what it is. I'm not even sure if he's reset the time period of keeping time travel in your head or not, so keep quiet until July, or maybe for the next year, just to be safe. I'm only able to leave this message because I found your interloper, who happened to offer to sneak this in for me.

Good luck!

—The Author of Hairy Snout, Human Heart

Remus grabbed the nearest copy of the Daily Prophet and checked the date: 16 February 1965. Young Remus and Romulus would be turning five soon...

His heart sank: Greyback would be attacking tonight. Yes, it was possible that something Remus had done in 1960 had changed things, but he couldn't count on it. He had to warn Dad.

He Apparated to his childhood home—well, his first one, anyway—and knocked loudly. Remus waited in agony until, finally, Dad answered the door.

"Are you the man who claimed that the Muggle tramp was actually a werewolf in that committee?" Remus asked.

"I am," Dad said.

Remus felt his heart jolt: the timeline hadn't changed.

Dad narrowed his eyes at him. "You're a werewolf too."

Of course. If Greyback couldn't fool Dad, what were the chances of me doing so? "Look, I don't have much time—"

Dad pointed his wand at Remus.

"—but your family is in real danger."

"Stop talking, werewolf," Dad said coldly. That stung—as far back as Remus could remember, Dad had always been a supporter of werewolf rights. But, of course, Dad still didn't have the motivation to do so yet, and was still just parroting prejudices of most wizards—just like what got him in this mess in the first place.

"Fenrir Greyback wants his vengeance and will take it out on your family," Remus continued.

Dad just shot an immobilizing jinx at him and Apparated them both to the Ministry's detention hall. There they had rooms where a werewolf could safely transform, but Remus had always tried to make other arrangements when he could. The place was...unpleasant to be in—and that was before he started having flashbacks of some particularly bad nights.

"So did you try catching that Muggle who no one but you is convinced is a werewolf?" the wizard manning the place asked as Dad brought Remus forward.

"I think this is a werewolf friend of his," Dad said. "I'd feel safer if you kept him here tonight."

Remus wished he could scream about the werewolf that Dad should really be worried about, but his mouth was frozen shut and he didn't have the energy at this time of the month to wandlessly dispel the jinx. Dad followed the detention wizard and floated Remus into a tiny warded cell.

The room had stone walls that had been defecated on countless times—magic might have been able to get rid of the smell, but no one had ever bothered to do so. The door had magically reinforced metal bars through which the guard could observe everything. There was also several invisible wards that would prevent anything from leaving the cell—physically or magically—when the door closed. The only way out was a narrow slot that led to an old basket outside the door, which happened to be where the detention wizard placed the wand he confiscated from Remus.

"If you want anything to be safe in the morning, stick it through the slot and it'll be in the basket when you leave," the wizard said after he locked the door. "Don't try sticking your hand through there. It hurts worse than a bludger to the groin."

Dad Disapparated and Remus regained control of his limbs. Remus started to take off his cloak when his hand touched a book in his pocket: Hairy Snout, Human Heart. It would be a few minutes before moonrise, so he figured that he wouldn't give the detention wizard more time looking at a naked man than he had to. Remus was only going to reread some of his favorite passages, but then it occurred to him that the author might have left something else for him to find that might help. He flipped through, looking for anything new, and found a quick note scrawled above the afterword.

Since you would have been taking your potion if you hadn't just gone through a time skip, I went under Blair's nose to retroactively make it so.

All my love,

the interloper

So Remus' body would react like he had taken his potion all week? That changed everything: if he could be there when Greyback arrived, Remus could fight him without worrying about accidentally injuring any of the Lupin family. He had to get out of this cell and back to his old house.

"Am I really going to be here all night?" Remus asked the detention wizard. "I have things I really need to do."

"It's not my business to question these things. If the moon hits and you're not a wolf, I don't see any reason to keep you here. If you are one then we'll register you when you come to your wits in the morning." The wizard walked off to check on the other werewolves that had been locked up.

Remus had an idea. It'd be cutting it close and might not work at all, but it was the best chance he had of helping his family tonight.

It takes about 50 seconds for the transformation from man to wolf, almost all of which involves a lot of panting, grunting, screaming, and howling. But it is only in the last 15 seconds that it is obvious that the person in front of you is not merely unwell but undergoing a full-on biological shift. The Wolfsbane Potion did not make this process any less painful, but when your mind is still your own, you actually have the capacity suppress the animal instinct to cry out while in pain. At least until the human instinct to cry out in pain takes over.

"The moon is about to rise," the detention wizard said when he returned. "If you're a werewolf, you'll probably want to disrobe and put all of your belongings in the basket."

"I don't want to go to the hassle of taking off my clothes just to put them on again later," Remus said.

"You know, it has happened that people have been bitten and they block out the memory of the experience until they turn on the next moon. You sure you don't want to make sure that you don't ruin your things?"

"No, really, I'm fine," Remus insisted. Right then, Remus felt the crushing weight of the moon on him. He did his best to not flinch. The werewolves in the nearby cells started choking in pain. Remus had to differentiate himself from them as much as possible, so he started talking.

"You know, I don't know very much about werewolves," Remus lied as he refused to let the fire filling his veins get the best of him. "By some odd coincidence, I actually started reading this book that just published: Hairy Snout, Human Heart. I'm not very far, but it's quite interesting."

"It's about werewolves then?" the detention wizard asked.

I am feeling fine, Remus told himself. My veins are not on fire and I am only believing that they are because I am reading an incredibly vivid novel on a dare. Even the moon is just a figment of my imagination. Out loud, he said, "it's actually just about one werewolf in particular. It's an autobiography. I just got to the part where..." His voice was starting to get strained, so he shook his head like he'd realized the detention wizard wasn't all that interested. Which he probably wasn't.

The sounds of the werewolves in the other cages got louder. One even started howling even though he couldn't possibly be looking like a wolf yet, beyond the dilated pupils.

"You're not a werewolf," the detention wizard said.

Remus shook his head, no longer trusting his throat to make normal human sounds. Any second now, claws would be coming out of his fingers and toes.

The detention wizard opened the cell door. Remus walked quickly out of the wards, grabbed his wand, and Apparated, hoping to Merlin that he didn't splinch himself.

He rematerialized back in front of his old house and crumpled to the ground, finally letting the pain be acknowledged. Fire fire fire as his bones deformed into inhuman shapes. A faint scent he despised hit his nose: Greyback. It was tonight.

He looked around, not seeing Greyback, but there was an open window in the Lupin household. He's already in there.

Remus climbed through the window after him, despite his transformation not being completely done yet. Greyback wouldn't be done changing yet either, and Remus needed to be ready for him.

Greyback turned as Remus hit the floor of his old room. There were two beds in here now, one for Young Remus and the other for Romulus. Both were asleep, but they wouldn't be for long.

Remus leaped over Greyback, putting himself between the vengeful werewolf and the boys. Greyback growled at him, and Remus growled back. Greyback lunged towards Remus and their fight began in earnest.

Remus had never been particularly strong, not in his human form compared to other humans, and not in his werewolf form when compared to other werewolves. Most of this was conscious on his part: if he didn't make his human body strong, his wolf side might be weak enough that it could be fought off if any humans were unlucky enough to come across him. But now, as he fought the werewolf who prided himself on his strength, Remus wished that he had done something to make himself more on the brawny side.

The bedroom door flung open. "No! Everte Statum! Depulso! Expulso! Confringo!" Dad. Remus jumped back towards the window to make it more obvious that it was Greyback that Dad should focus his spellcasting on instead of him. Dad, for his part, looked amazing—Remus didn't remember a time when he saw him flick his wand so fast. As soon as Greyback hit the windowsill, Remus jumped on him, taking both of them outside.

Remus growled and slashed at Greyback—even though the latter was weakened by Dad's attack, he was still a threat. These humans are mine, Remus tried to convey, but Greyback had no intention of backing down to some scrawny wolf who thought himself an alpha. Remus realized that the best way to deal with this was to get Greyback to chase him, so he could lead the werewolf away from any humans that might be in danger tonight.

So Remus peed on Greyback's face and ran.

"Remus, Romulus, are you sure you're not hurt anywhere?"

"Yes, Daddy," both boys replied for the umpteenth time. But even then, Lyall had had Remus and Romulus take off their pajamas as he inspected every square inch of their bodies. They were both lucky that it looked like neither werewolf had so much as brushed up against them. They were lucky that the smaller werewolf had decided to fight the bigger one instead of preying upon the humans in the room.

Lyall couldn't figure it out: why was the smaller werewolf going against the basest of the beast's instincts just to pick a fight with the other wolf? Could the dissension between the two really be that great? But if that was the case, then why would they try to attack Lyall's family together? Did they assume that their wolven selves would set aside their differences when in the presence of tasty humans? Maybe, but Lyall thought that such an assumption would have been too risky, especially given what happened.

"Daddy," Remus said, "I'm sleepy."

"Me too," Romulus added.

"Okay, okay," Lyall said, "we'll put your pajamas back on and you can go back to bed." That took the usual several minutes, but eventually Lyall's boys were back in their beds and safe. He hoped.

Lyall went to the window to add some more security charms, but as he did so, he saw the smaller werewolf had returned, though it only appeared to be sitting at the curb passively, looking at something on the ground...was that a book?

The werewolf then noticed that someone was there and turned to look at Lyall in the window. It nodded towards him, looked up and down the street, then went back to looking at the thing in front of it.

What in Merlin's name is going on here? Lyall wondered, unable to stop looking at the creature in front of his house—whether in caution or fascination, he wasn't sure himself.

Then the werewolf turned a page of what was indeed a book with his snout. It's reading. A werewolf is reading on my curb.

Lyall went back to his bedroom, where his wife was drinking some tea to quiet her nerves. She handed a second cup to Lyall, but he didn't drink, instead setting it on the nightstand. "Hope, I need you to look at something outside. Tell me that I'm not imagining it."

"You need a Muggle's perspective, hmm?" Hope asked as she squeezed his hand.

"Maybe. At the very least, you'll be able to recognize it later: it's one of the werewolves that attacked us."

Hope nodded solemnly and followed Lyall back to the window. "I thought you said that werewolves lose their minds when they transform," she said.

"They do," Lyall confirmed.

"Then why is—"

"That one reading?" Lyall finished. "I have no idea. When it changes back into a person, I'm going to go ask."

"Lyall, be careful. Even in human form, he could be very dangerous."

"I will," Lyall said, kissing Hope's forehead. "Now go back to bed. I'm going to be up for a while longer to make sure our werewolf trespasser doesn't get up to anything."

Turning back into a man tended to be less painful than the reverse. It was more like the tension of a rubber band being released than the burning preparation of sliding into a new form, but that didn't mean that the experience was in any way enjoyable. Interestingly, the perception of pain was higher when Remus had taken his potion, as there was no wolf-brain to take any of the reversion ache upon it.

Dad came outside just as Remus started to feel like his normal, exhausted self. "You?" he cried.

"Yes, me," Remus said. Grovelling apologies or angry "you should have listened to me"'s weren't going to help anyone right now, so he decided to take on Old George's matter-of-fact attitude about it all. Maybe Dad would even believe him. At the very least, this way he wouldn't have to expend as much emotional energy.

"But you were in the detention cell!"

"I got out early for good behavior," Remus deadpanned. "Look, we can continue your yelling at me, but my clothes are in shambles from last night, and I'd appreciate it if I could borrow a set of robes or even just a blanket, so your neighbors don't have to see the naked man in front of your house."

Dad stared at him a moment, before shaking his head and summoning a throw blanket from inside—one that he remembered accidentally destroying as a kid. Remus took it and wrapped it around his waist. "Thank you."

"What were you doing in my house last night?" Dad asked.

"I tried to warn you about Greyback but you wouldn't listen," Remus said. "I realized I'd have to stop him myself, so I did so—though it was thanks to your wand that we were successful in getting him out, so thank you for doing your part."

"You could have hurt my sons," Dad said.

"There was very little danger of that happening," Remus said. "I can keep my mind during the moon."

"That's impossible," Dad said.

"It involves a potion that took me nearly a year to learn how to make, but it works," Remus said. "I wouldn't have been able to come if it had failed. But, last I checked, the potion recipe needed to be developed more if we want to use it for a more generalized consumer than just me, so I'm the only one who has even heard of it yet."

"And does that other werewolf know about this potion?" Dad asked.

Remus shook his head. "I don't socialize with other werewolves if I can help it."

"Then how did you know my family would be targeted last night?"

"I had a strong hunch based on my past experiences," Remus said, leaving it at that.

Dad scrutinized him. "Why were you so determined to 'help' me? I thought I made my position on werewolves clear."

"You don't have a position on werewolves yet," Remus retorted. "You just have awareness of one side of the story, which is largely made by people as ignorant as you. Here, read this," Remus handed Dad his copy of Hairy Snout, Human Heart. He'd skimmed through the whole thing, just in case any more handwritten messages had popped up, but there were none. The interloper's message in the afterword had disappeared too, though, so it was entirely possible that something else could appear later, but Remus knew that Dad would benefit from reading it so he could give it up. "It was written by a friend of mine and just published yesterday."

Dad read the book's description. "A werewolf wrote this? I thought you didn't talk to the others."

"He got stuck in a Well," Remus said, knowing that Dad would have no idea what he really meant. "And I couldn't get him out. I barely even knew him, really, but I've read his story more times than I can count. Changed my life."

"Then I won't deprive you of your pre-publication copy and I'll just get my own," Dad said, handing the book back to him. "What's his name?"

Remus choked out a laugh. "And that's the saddest part: I never got the chance to find out."

Fenrir Greyback slid out of his true form and back into a man. That other wolf had ruined everything, getting in the way of Fenrir's revenge on that Lupin. Fenrir, running on pure instinct, had chased the other wolf outside of the city and yet the scrawny creature had somehow managed to lose him. In any other case it would have been easy to track the other wolf down, but he'd marked territory on Fenrir's face, throwing off his sense of smell.

Still, the other wolf's bizarre behavior wasn't the only thing Fenrir was preoccupied with—it was the wolf's scent itself. It smelled a lot like Fenrir's own, and there could only be one possible reason. That other wolf had to have been the one who had bitten him all those years ago.

It just figured that the unknown wolf that had given Fenrir his greatest gift turned out to be a lunatic beast with no idea how to be a werewolf.