TheFanficGOD
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CASS171- Rat
🕑 Added 2025-10-30 18:25:42 +0000 UTCCassian slammed the door with the side of his boot, as he strode in ahead of Bathsheda.
"How the hell did he get into Gryffindor?" he snapped, already pacing. "It's a bloody tower. With a password. And a portrait that bites."
Bathsheda dropped her bag onto the nearest chair. "I don't know. I've got four theories and they all start with 'we're surrounded by idiots.'"
"He either didn't know which bed Potter slept in, or he didn't care."
They'd just come from a disaster of a meeting. Sirius had managed to break into Gryffindor Tower and gone straight for the wrong bed. Nearly shredded Weasley's mattress.
Snape wasted no time. Marched into the staff room and pointed a trembling finger straight at Remus. Accusations flying. Dumbledore said nothing, sat there like an ornamental gargoyle. McGonagall muttered something about caution, as if that had done anyone any bleeding good so far.
Hogwarts was held together by spells, grit, and pure bloody denial at this point.
He dragged a hand through his hair. "He went for the Weasley kid. Not even Potter. And Remus looked like he was going to be sick."
"Snape practically asked to check his pants for Dark Marks," she muttered.
Cassian gave her a look. "Are we sure this is about Sirius."
She rolled her eyes.
Cassian opened the map and tapped it. They were in class when it happened. He and Bathsheda both. No one was watching the map.
Whether it was a wild stroke of luck or Sirius actually knew they had a way to track him, he couldn't tell. He doubted it, though. Timing it for when most of the castle was locked up in classrooms was the smart move, less traffic, fewer eyes. But if Harry was in class too... what was the point? He wouldn't have been in the dorm.
"We need to constantly watch it."
She didn't argue. Just nodded, already pulling the scrolls off her desk.
Cassian leaned back in his chair, arms crossed. "I'll string it to the clock tower if I have to. Charm the bloody gears to ring when something twitches."
Bathsheda didn't look up. "Or we rotate. One of us checks every hour. No gaps."
He let out a short breath. "And remind me why we didn't hand this over to Dumbledore again?"
Her eyes flicked to him. "Because he'd lock it in a drawer and say 'trust will see us through.'"
"Right. That."
He stood, wandered over to the desk where their notes on the map were stacked in uneven piles. One of the corners had been singed, probably from when he'd tried a tracing charm too close to the inkwork.
"He tore through the bed," Cassian said, flipping a page without really reading it. "Weasley's. Not Potter's."
"I know."
Cassian frowned, eyes still fixed on the parchment. "Baths... there's something off here."
She didn't look up yet. "Define 'off.' I've already got ten things on the list, including the fact I haven't slept in two days."
He pointed at the map, jaw tight. "I don't think Sirius killed Pettigrew."
That got her attention. She stood from the chair, closing the distance to make sure she wasn't hearing things. "What?"
Cassian pointed at a name. "Remember what I said about the map showing people who shouldn't be here? Twins thought it glitched sometimes. That it wasn't perfect. I think the map's perfect."
Bathsheda didn't say anything. She followed the little name as it veered sharply left, paused near the Great Hall, then zipped away again. It hadn't blinked out once.
She folded her arms. "You're telling me we've had a dead man doing laps around the castle?"
"I'm telling you someone we thought was dead isn't," he said. "And if Sirius Black was after him, then this changes everything."
"Shit," she muttered. "That means Black's not here for Harry."
Cassian glanced sideways at her. "No. He is not."
Bathsheda bit the edge of her thumbnail. "Why Weasley's bed then?"
He tapped the map again. The name was darting along the corridor, weaving neatly past every student, no one even sparing it a glance. Too fast. Too nimble.
"Because he's a pet."
Her head snapped round. "Percy's old rat. Still lives."
Cassian nodded, eyes still on the name. "I think so."
She stared at him. "First Sirius, now Peter? Both Animagi? Do you know how mental that sounds? Who's next? James bloody Potter turning into a sofa?"
Cassian's brow furrowed, but the corner of his mouth twitched. "I think all three of them were Animagi. To help their fourth friend."
Bathsheda didn't answer. Her gaze drifted toward Remus's quarters down the corridor, just in time to see Snape disappearing inside.
She didn't blink.
"He is..."
Cassian said nothing for a moment. Then, "I believe Remus Lupin is a werewolf."
She turned slowly. Blank expression. That stillness people get when the obvious finally clubs them round the head.
"How can I be this stupid," she muttered. "It was bloody obvious."
Cassian shook his head. "It's not that you're daft. Just no one expects the Headmaster to hire a bleeding werewolf."
She paced around "The way he disappears every month. The Wolfsbane deliveries. Even the damn tea scheduleβ"
"Laced with aconite. Yeah." Cassian flicked a page on the desk. "Figured it a while back."
Her jaw twitched. "And you didn't tell me?"
He wrapped his arms around her waist, tugging her in. "Was trying to be sure before pointing fingers."
Bathsheda leaned into him, chin brushing his shoulder. "You were right."
She whispered, "If the Ministry finds out..."
Cassian waved her down. "They will, eventually. I think half the staff already know, or at least suspect. Dumbledore shielded him. That's the only reason he's here."
She stayed there for a second, then added, dry, "The girls were gossiping about Snape and Lupin. Something about hate turning into longing stares."
Cassian snorted. "Oh, that I have to leak to Snape."
Her hand slid under his robe and smacked his ribs. "Don't you dare."
"I'll do it anonymously," he said, already plotting. "Leave him a note. 'Dear Severus, your stares are growing suspicious. Sincerely, the corridor ghosts.'"
She tilted her head back, mouth twitching. "You're a menace."
"Please," he muttered, "I'm a public service."
He moved to the table, peeling back the top sheet of notes they'd been scrawling on all week, adding, Pettigrew, timelines, Hogwarts ward gaps, map anomalies.
Bathsheda leaned on the other side of the desk, her arms folded tight. "So, if he's the rat, and Black came here to kill him..."
"Then the last twelve years of Ministry records are built on shite."
She didn't reply. Sank into the nearest chair, eyes darting over the map like she could force it to lie. "If that's true, then Pettigrew's been in Gryffindor Tower for years. Slept in their dorms. Ate their food. Followed them around."
Cassian's voice was flat. "And listened."
Her eyes cut to him. "Spying? For who?"
He tapped the desk with one finger. "At first? For survival. Then, I don't know."
Bathsheda blinked, then swore under her breath. "Merlin help us, Cass. If you're right, he's been curled up on Weasley's pillow while we've been congratulating ourselves on clever wards."
Cassian's mouth twitched humorlessly. "Rat at the table, rat in the bed, rat in the bloody dormitory. He's had better intelligence than half the Auror Office for twelve years."
He then glanced at her. "We'll need proof."
"We've got proof," she said. "The map."
"Map shows a name. Doesn't show what body it's tied to. For all they'll know, he's got a nephew. Or a ghost."
She frowned, eyes narrowing. "We need to catch him."
He nodded. "Alive."
Her mouth pulled tight. "And make sure the Weasleys aren't caught in the crossfire."
She leaned closer to the map again, tracing Pettigrew's little scuttling path. "If Black knows, he'll try again. He won't stop."
Cassian's jaw tightened. "There has to be a reason for this enmity. Pettigrew has to be caught in a body, not just a name. Otherwise, we're shouting ghosts at the Wizengamot. Black should know it too."
She stared at the name darting back and forth. "We're building a trap for a rat."
Cassian smirked thinly. "History's oldest game."
He grabbed the chalk and scratched out a list,
Pettigrew
Animagus - Rat
Gryffindor Tower
Possible extraction plan?
He underlined the last bit, twice.
Bathsheda sighed. "You ever feel like we're babysitting history while it throws a tantrum?"
Cassian flicked her a look. "No. I feel like I'm elbow-deep in a very old, very ugly lie."
He paused, then added, "And babysitting."
She didn't argue. Just muttered something sharp under her breath.
"What was that?"
"If I end up hexing a rat in a boy's pyjamas, I'm blaming you."
Cassian shrugged. "Wouldn't be the weirdest part of the week."
His fingers hovered over the map, but he wasn't watching it anymore.
Bathsheda turned slightly. "What is it?"
He didn't answer straight away. Just stared at the parchment.
She reached out, fingers brushing over his. "Cass."
He let out a breath. "What if Sirius didn't betray the Potters?"
She blinked. "I doubt that's open to debate, love."
His brow tightened. "Is it, though?"
Sirius Black. Harry Potter. Something about a godfather. His mates from past life... They'd spoken of him not like a villain, but someone who stayed in the boy's life. Was he forgiven by Harry? He doubted. He knew the boy. If that was even partly true... then maybe Black hadn't betrayed them at all.
Bathsheda frowned. "Cass, the whole bloody world thinks he handed them over."
"I know. I know." He tapped the edge of the table with his knuckles. "But think about it. Why the hell would Peter Pettigrew live twelve years in Animagus form? Why not just disappear? Why stay in the one place Sirius could possibly find him? Why hide that hard if he wasn't the one with something to hide?"
Her gaze went back to the map.
"I don't think Sirius betrayed them," Cassian said, finally. "I think Peter did. And Sirius tried to kill him for it."
He didn't say the next part.
That if Sirius had been thrown into Azkaban for murder and betrayal and spent twelve years listening to the screams of things that fed on guilt, and hadn't even done it...
No wonder the man was mad.
Bathsheda murmured, almost to herself, "If you are right and we pull this off, history changes overnight. Black exonerated. Pettigrew exposed. The Ministry stripped bare."
Cassian's hand hovered over the map. "History doesn't change. It just waits for someone stubborn enough to shove it back into the light. Good thing I am very good at Lumos."
The map shimmered again. Peter Pettigrew skittered down the hall beside the Great Hall.
He watched it. Let the silence hang.
"Right," he muttered. "Let's catch a dead man."
Comments
TheFanficGOD
That anger will surface, I just wanted to avoid repetition, I promise. Also, canon divergence is coming. When it hits, it'll go completely sideways, which is why it's taking its time. I've mentioned this before, but I like the plot to follow an organic path. Since Cassian isn't familiar with the original events, yes, his presence will change things, but it shouldn't happen suddenly. His involvement will gradually shift a few key points before eventually derailing the canon entirely.
TheFanficGOD
π€£π€£π€£ Why not add part of his soul so he can judge them for eternity
SwiftFate
I do hope this leads to some proper canon divergence. Thought that was supposed to happen last year, but this one is panning our pretty much exactly the same regardless, just throwing the chaos of Cassian in the mix. I'm half expecting the same results even with their involvement, which then just leads to the same stuff with Peter helping revive Voldy etc etc. Don't get me wrong, I love Cass being an unreliable narrator when it comes to HP canon and not really having a clue aside from small hints from his friends in the past, but this revelation about Peter should have happened the moment he got the map and saw a literal dead man next to Ron Weasley in the middle of the night. And with how protective he is of these kids, I'd expect some FURY from him. An adult, sleeping with children for years. He should be on a war path, not trying to be sneaky about it. Surely he has the ability to immediately incapacitate a Rat in the open.
Marcia McGinley
Loved the chapter! Also, I think Dumbledore would make a wonderful ornamental gargoyle and that it would be a brilliant way to immortalise him (should events take their canonical course).
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