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“You’re telling me,” James said slowly, eyes wide behind his glasses, “that Peter is still a rat.”
Sirius was pacing, hair wild even by his usual chaotic standards. “Yes, Prongs, that’s exactly what I’m telling you! He’s been a rat since breakfast! I thought he was just having a kip, but no—he squeaked at me when I asked if he wanted toast.”
From the edge of the bed came an indignant squeak.
James looked down at the small brown rat sitting neatly on one of his Quidditch socks. “You don’t look stuck to me,” he said. “You look perfectly fine.”
Peter squeaked again, louder this time, and thumped his tiny paw against the floor—a gesture impressively human for a rodent.
Sirius threw up his hands. “See? He wants to turn back! He just can’t!”
“Maybe he’s doing it wrong,” James said, crouching. “Pete, you’ve got to concentrate. Think about your fingers, your face, and your stupid haircut, yeah?”
Peter’s whiskers twitched. His little pink nose scrunched. For a moment, he glowed faintly, and then… nothing.
Sirius groaned. “Brilliant. Wormtail’s going to be a permanent pet. What are we meant to tell McGonagall? ‘Oh, sorry, Professor, one of our best mates accidentally became a rodent and we can’t un-rodent him?’”
James grinned. “To be fair, she’s always said we were a bad influence on each other.”
“She didn’t mean this kind of influence, Prongs!” Sirius cried, flopping onto his bed dramatically. “Merlin’s beard, what if he gets eaten? Filch’s cat’s still on the prowl. Or worse—what if Snivellus finds him?”
Peter made a squeak that could only be described as a rat-sized gasp of horror.
“Right,” James said, straightening up. “Then we’re on rat-sitting duty until he figures it out.”
By lunchtime, it was already going spectacularly wrong.
The Marauders had agreed to tell McGonagall that Peter was “sick” in bed with a dreadful stomachache. Sirius had delivered the excuse with an Oscar-worthy display of concern that had fooled precisely no one. McGonagall’s lips had thinned, but she’d only said, “Very well, Mr. Black. I shall expect a note from Madam Pomfrey.”
Now, during Transfiguration, James had tucked Peter safely into his robe pocket. For a while, things went smoothly. McGonagall was lecturing about the dangers of partial animal transformations—which felt painfully on the nose—and James was trying to take notes without moving too much.
Then came a soft squeak, a tickle against his chest, and suddenly a blur of brown fur shot across his desk.
“Mr. Potter,” McGonagall said sharply, one eyebrow arching high enough to reach the rafters, “would you care to explain why there is a rat in my classroom?”
Sirius, sitting beside him, immediately choked on a laugh and tried to disguise it as a cough. “Pet project, Professor?”
“Ten points from Gryffindor,” she said, eyes like daggers. “And I suggest you remove your pet before I transfigure it into something less distracting.”
James caught Peter mid-dash and shoved him back into his pocket, muttering an apology while Peter bit him on the finger in protest.
As the class ended, McGonagall gave the two of them a long, suspicious look. “Do tell Mr. Pettigrew I hope he recovers swiftly from his sudden illness,” she said dryly. “And perhaps remind him that Transfiguration is not best practiced unsupervised.”
Sirius gave a nervous grin. “Absolutely, Professor. Wouldn’t dream of it.”
Her eyes narrowed. “I’m sure you wouldn’t.”
The moment the door shut behind them, Sirius burst into laughter. “You should’ve seen your face! I thought she was going to make him into a teapot!”
“She might have,” James muttered, examining his bitten finger. “And whose fault would that have been? You’re supposed to be on pet-sitting duty too, Pads!”
“Excuse me, I’m the fun sitter,” Sirius said airily. “You’re the responsible one. That’s how it works.”
“Since when?”
“Since about two minutes ago.”
Peter poked his head out of James’s pocket, squeaking in pure exasperation.
“Look, mate,” James said, sighing, “just try again. Think human thoughts. Fingers, arms, that unfortunate fringe.”
Peter squeezed his eyes shut, concentrating hard. There was a faint shimmer of light, and then instead of a human, he turned into a slightly larger rat.
Sirius howled with laughter. “He’s bigger! Oh, that’s fantastic. An upgrade!”
“Not helping!” James swatted him. “We can’t keep him like this all day!”
“Oh, can’t we?” Sirius said innocently. “He’s adorable! Maybe we should get him a tiny jumper.”
Peter lunged and bit him on the thumb.
“Oi! Fine! No jumper!” Sirius yelped, shaking his hand. “Ungrateful rodent.”
By dinnertime, half the Gryffindor common room had heard that James and Sirius were hiding a mysterious pet. First-years whispered excitedly, and even Lily Evans had stopped by their table, eyes narrowed.
“Why do you two look like you’re smuggling something?” she asked.
“Because we’re not,” Sirius said smoothly, which, like his performance to McGonagall that morning, wasn’t even remotely convincing.
Lily crossed her arms. “Right. Well, whatever it is, keep it away from the food. And tell Peter I hope he’s actually ill and not skipping lessons again. He’s been acting… strange lately.”
Sirius and James exchanged a quick glance. “Of course,” James said quickly. “We’ll, uh, pass that along.”
The moment she walked away, Sirius exhaled. “Close call. Evans has eyes like a hawk.”
James leaned in. “We’ve got to fix this, Pads.”
They slipped out of the Great Hall and sprinted up to Gryffindor Tower, laughing breathlessly by the time they reached the dormitory. Peter wriggled free of James’s robes and scampered across the bed, tail flicking irritably. He perched himself on the table, grooming his whiskers like this was perfectly ordinary.
“You know what?” Sirius said. “Maybe he’s just overthinking it. Stop worrying, Wormtail. Picture yourself this morning—human form, two arms, two legs… same tragic haircut.”
Peter froze, squeaked, and then—in a flash of light, he was sitting on the table, very much human again… and very much naked.
“Merlin’s pants!” James yelped, throwing his cloak over him.
Sirius collapsed, laughing so hard he nearly fell off the bed. “I said two arms and legs! I didn’t say clothes!”
Peter groaned, clutching the cloak tighter. “Why does this always happen?!”
Sirius wiped tears from his eyes. “Because when you transform, your clothes don’t come with you, genius! It’s Transfiguration 101!”
“Don’t tell McGonagall about this,” Peter pleaded. “Please.”
“Oh, we’re definitely telling McGonagall,” Sirius grinned. “She deserves to know how her top students spent their day.”
“Top students?” James muttered. “You almost set his tail on fire at one point.”
“Minor detail.”
Peter glared at them both, still wrapped in the cloak. “You two are the worst pet-sitters ever.”
James grinned. “Nah. You’re alive, un-eaten, and only slightly traumatised. That’s a win in my book.”
Sirius ruffled his hair. “Anytime, Wormy. Next time, maybe you can pet-sit me.”
Peter looked horrified. “Absolutely not.”
As laughter filled the dormitory, the door creaked open. Remus’s voice drifted in—soft, tired, and faintly amused.
“Do I even want to know what you three have done this time?”
Sirius and James exchanged a look.
“Pet sitting,” they chorused.
Remus sighed, pinching the bridge of his nose. “You realise you’re all insufferable?”
“Utterly,” Sirius said cheerfully. “But we’re house-trained.”
Remus snorted despite himself. “That’s debatable.”