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Sure enough, the Weasley twins were cunning enough to scatter food scraps along the floor, misleading Mrs. Norris and leading Filch astray.
Erwin watched the twins with growing amusement.
When he'd watched the films in his previous life, the Weasley twins had always stood out.
As Hogwarts' reigning mischief-makers, each movie showcased their ridiculous antics.
Sadly, Fred had died in the end.
Only one twin remained, alone from that point forward.
Erwin had regretted that outcome in his previous life, but it didn't stop him from preparing to mess with them now.
Who told them to disrupt his night tour plans?
Watching the twins walk ahead, completely oblivious to the impending danger, Erwin allowed himself a wicked smile.
With a flick of his wand, he targeted a suit of armor standing guard in the corridor.
The helmet suddenly toppled and crashed to the ground with a tremendous clatter.
BOOM!
In the empty corridor, the sound echoed dramatically.
The twins, who had just passed by, jumped in fright.
"W-what?"
"What happened?"
They spun around quickly to see what had happened, but found only a fallen helmet on the ground with no one else in sight.
In the distance, Mrs. Norris's distinctive meow and Filch's heavy footsteps grew audible once more.
Panicking, the twins didn't bother investigating further.
They hurried toward the nearby staircase and climbed rapidly to the fourth floor.
Erwin held back his laughter, carefully muffling his footsteps as he followed.
"Aha! Students on a night tour. I must tell Filch."
Suddenly, Erwin heard a voice from the corner of the fourth-floor staircase. Peeves had discovered the twins.
****
Peeves had been roaming the castle as usual, searching for opportunities to cause mischief and chaos.
When he'd reached the fourth floor, he'd heard the sound of hurried footsteps and floated toward the noise.
The fleeing twins appeared before his eyes, filling him with delight.
Although he and the Weasleys shared a certain kinship, both loving mischief, that didn't mean he wouldn't trick them.
There could only be one king of mischief at Hogwarts, and that was Lord Peeves himself.
"Hee-hee. Weasley brats. Caught by the great Peeves, are you?"
"Just say it: 'The great Lord Peeves is the most mischievous person at Hogwarts.' Say that, and I'll consider letting you go. How about it?"
Peeves stretched his mouth into a grotesque grin, looking tremendously proud.
The twins exchanged glances.
Fred looked at Peeves with an expression of mock solemnity.
"The most…"
"Mischievous person at Hogwarts is…" George continued seamlessly.
The twins looked at each other once more, then burst out laughing and spoke in perfect unison.
"Is clearly us."
With that, they bolted to the right, leaving Peeves fuming and stomping in midair.
"Pfft."
Erwin couldn't contain himself any longer and laughed aloud.
The twins were hilarious, even in this situation; they could still taunt Peeves.
"Who's there?"
Peeves startled at the sound of laughter.
He immediately realized another student was hiding nearby and began looking around suspiciously.
Erwin wanted to see what other chaos the twins might create and had no desire to be haunted by Peeves.
Noticing chalk pieces scattered on the floor, likely what Peeves had been planning to throw at students, he pointed his wand and whispered…
"[Oppugno]."
The fallen chalk transformed into projectiles, launching at Peeves like cannonballs, one after another.
Peeves shrieked in terror.
These chalk pieces didn't pass harmlessly through his spectral body; they actually hurt him.
With a wail, he fled down the left corridor.
Erwin deliberately controlled the chalk's trajectory, forcing Peeves in the opposite direction from the Weasleys.
But the corridor on the fourth floor, to the right, why did it seem so familiar?
Suddenly, Erwin's expression shifted.
Dumbledore had explicitly forbidden students from going in that direction during the opening ceremony. That was where it was.
'This is the location for the first-year quest. If the twins break into that abandoned classroom, they'll encounter Fluffy, the three-headed dog guarding the trapdoor.'
Without knowing the creature's weakness, encountering it would be genuinely dangerous.
Hadn't a certain Potions professor been bitten on the leg there?
Thinking of this, Erwin didn't hesitate.
He cast a leg-strengthening charm and hurried toward the right corridor.
Sure enough, after moving a short distance, he spotted the twins studying how to open the door to the abandoned classroom.
Fred used [Alohomora], and the door swung open in response.
The two rushed inside excitedly.
Erwin smacked his forehead.
Dumbledore's defenses were pathetically weak; he hadn't even set a counter-charm for the unlocking spell.
'Are you deliberately making it easy for Harry to enter?'
He hurriedly followed the twins inside, then saw an enormous three-headed dog lying on a trapdoor.
Its three heads drooped quietly, as if sleeping.
A terrible stench assaulted his nostrils, and Erwin quickly held his breath.
'Good grief, this three-headed dog even has a biochemical attack?'
The twins weren't as quick to react.
When the smell hit them, one of them, Erwin, couldn't tell if it was George or Fred, blurted out loudly.
"It stinks."
The exclamation rang especially clear in the quiet environment.
Instantly, all three heads of the dog snapped open simultaneously.
Two heads fixed on the twins standing before it, while the third turned toward Erwin, standing farther back.
Naturally, the Disillusionment Charm didn't mask scent; it merely blended the caster with the surrounding environment visually.
Suddenly, the middle head roared and lunged at the frozen twins.
Their reactions weren't slow.
Both drew their wands instantly and cast [Impedimenta] in tandem.
Unfortunately, they were only third years, and their magical power wasn't particularly strong.
The three-headed dog stumbled briefly, then continued its attack like any normal aggressive dog.
Erwin abandoned all pretense of hiding and revealed himself.
"[Flipendo]."
He put everything he had into the spell.
A red beam shot from his wand tip and slammed into the three-headed dog.
BOOM!
As if struck by a speeding truck, the creature flew backward and crashed into the classroom wall with a thunderous impact.
The twins were obviously startled; they hadn't expected a third person to be present.
Erwin had no time for explanations.
The three-headed dog possessed high magic resistance, and a single Knockback Jinx wouldn't cause lasting damage.
'We need to put it to sleep quickly, or the noise will attract professors, maybe even Old Dumbledore.'
Erwin's mind raced.
He shouted at the twins.
"Quick, sing. Sing that song you performed at the Sorting Ceremony."
Though puzzled, the twins recognized that Erwin had a purpose.
Without hesitation, they began singing their funeral march version of the Hogwarts school song.
The three-headed dog's movements began to slow as the melody filled the air.