"Lumos!"
At Hermione's incantation, a small sphere of light rose from her wand tip and illuminated the entire compartment.
A scraping sound came from beside the window.
Ron was desperately rubbing away the condensation, trying to see outside.
"There's something moving out there," he muttered while squinting into the darkness.
"I think someone's getting on the train…"
But before he could finish, everyone in the compartment had already spotted one of the intruders.
A tall figure in a tattered black cloak slowly emerged in the doorway.
Its face was completely hidden beneath a deep hood.
It floated there silently.
A gray, shriveled hand—more like a corpse's claw than a living limb—slipped from beneath the cloak and pointed toward the compartment several times, as if counting the occupants.
Then the hand withdrew.
The creature took a long, deep breath.
"Hhhhhhhhh…"
An unnatural rattling sound echoed from beneath the hood.
As it inhaled, the temperature in the compartment plummeted.
This was not imagination.
Frost visibly spread across the tables and seats.
Thud!
Harry collapsed unconscious almost instantly.
Ron began trembling uncontrollably.
Hermione raised her wand instinctively, intending to resist, but as the creature inhaled, every positive emotion inside her seemed to be drawn away.
She suddenly lacked the strength to do anything.
Ciri fared somewhat better.
Her arcane sword flashed with a Scorching Ray enchantment as she slashed at the creature.
The blade passed right through it.
No effect.
A Dementor.
The guards of Azkaban.
Unlike ordinary magical creatures, Dementors were a unique form of life.
Most forms of damage meant nothing to them.
They fed on positive emotions.
The more happiness they consumed, the more they multiplied.
A Dementor that fed enough would eventually divide and produce another Dementor.
Victims drained too thoroughly lost all joy, hope, and desire to live.
They became little more than walking corpses.
In a sense, their existence resembled ancient magical techniques that extracted negative emotions.
The difference was that Dementors consumed the positive ones instead.
And if they went too long without feeding, they would eventually starve.
Which was precisely why Azkaban always needed prisoners.
The Ministry and the Dementors had a simple agreement.
The Dementors guarded criminals.
In exchange, the Ministry provided them with food.
If the food ran out—
The Dementors became uncontrollable.
Like now.
Several half-starved Dementors had spotted an entire train filled with delicious young wizards and decided to sneak away from the main search party for a little feast.
Unfortunately for them—
Lewis had no intention of allowing it.
"Magic Circle Against Evil!"
A shimmering barrier spread through the compartment.
Even without knowing the Patronus Charm, Lewis possessed other ways to deal with creatures like these.
Dementors were inherently evil entities.
The moment the ward appeared, the Dementor was forced backward as though it had touched a burning stove.
It rolled through the air, unable to enter.
The creature circled outside the barrier but dared not approach.
Lewis wasn't satisfied.
Ordinary elemental magic had little effect on Dementors.
Force magic was different.
Force spells could strike incorporeal beings.
Ghosts.
Spirits.
And Dementors.
"Magic Missile Storm!"
Dozens of arcane missiles erupted from his wand like a torrential downpour.
They slammed into the Dementor one after another.
Its form shattered repeatedly.
Finally, unable to withstand the assault, it fled.
The immediate threat was gone.
Lewis bent down and grabbed several Chocolate Frogs from the pile of sweets they had purchased earlier.
"Eat these."
He tossed one to each person.
"They'll help."
He shoved one into his own mouth as well.
Warmth immediately spread through his body, pushing back the lingering chill.
Then—
A terrified scream erupted somewhere outside the compartment.
Ciri reacted instantly.
"That's Penelope!"
She sprinted into the corridor.
Lewis followed without hesitation.
Hermione wanted to go too.
Unfortunately, she had already been partially affected by the Dementor and still felt weak.
The corridor was chaos.
Dementors drifted in and out of compartments all along the train.
Their ghostly silhouettes looked especially horrifying in the darkness.
"There!"
Ciri pointed.
Four Dementors had surrounded Penelope.
The Ravenclaw Head Girl was trapped in the middle.
Ciri charged forward, but her enchanted sword once again proved useless.
"Use force spells!" Lewis shouted.
Then he rushed ahead himself.
There was no time for lengthy incantations.
He chose the fastest method available.
Psionics.
"Mind Blast!"
An explosion of psychic power swept through the corridor.
Unlike physical attacks, Mind Blast struck directly at consciousness itself.
Against creatures like Dementors, it proved devastating.
Several of them immediately lost cohesion.
Their forms scattered into mist.
When they finally managed to reform, they retreated in panic.
Lewis seized the opportunity and reached Penelope's side.
He stuffed a Chocolate Frog into her mouth.
Penelope instinctively grabbed his hand like a drowning person clutching a lifeline.
Strength slowly returned to her body.
"Dementors!"
"How are Dementors here?"
"Probably searching for Sirius Black," Lewis replied.
"Though it looks like the Ministry's pets have developed a few ideas of their own."
As he spoke, more Dementors drifted closer.
Many more.
Perhaps his psychic attack had genuinely hurt them.
Perhaps they wanted revenge.
Whatever the reason, a dark tide of Dementors now floated toward him.
"Lewis, watch out!"
Penelope shivered violently.
The temperature continued to drop.
Frost covered the windows.
"Don't be afraid," Lewis said firmly.
"Think about happy memories."
Yet even he could feel the cold sinking into his bones.
Mist clouded his vision.
"Force Sphere!"
This time Ciri had chosen the correct enchantment.
Her sword glowed with force energy.
Just then—
A voice echoed from behind them.
"Move along. None of us is hiding Sirius Black under our robes."
"Now leave."
Professor Lupin had arrived.
He stood with wand raised, staring directly at the Dementors.
The creatures ignored him completely.
Apparently they had decided that Lewis looked especially appetizing.
"Expecto Patronum!"
Silver light exploded from Lupin's wand.
A magnificent wolf burst forth.
Strong.
Graceful.
Powerful.
Wherever it ran, the Dementors retreated.
Unfortunately, only temporarily.
At least the fog around Lewis cleared.
"Expecto Patronum!"
Lewis decided to try as well.
With so many live targets available, it seemed like the perfect opportunity for practice.
A silver-feathered serpent emerged from his wand.
Not fully formed.
But recognizable.
The great winged snake soared down the corridor.
Beside him, Penelope stared at it in fascination.
The Patronus spread its wings and glided through the train.
Every Dementor in its path fled.
"Expecto Patronum!"
Another silver animal joined the battle.
A lion.
Ciri's Patronus.
The Lion Cub of Cintra had succeeded as well.
Not wanting to be left behind, Penelope attempted the spell herself.
She already knew the theory.
She had simply never managed to cast it.
"Expecto…"
"Expecto…"
She clenched her teeth.
Then she remembered Lewis rushing to save her moments ago.
"Expecto Patronum!"
A thin cloud of silver mist emerged from her wand.
It was progress.
Encouraged, Penelope tightened her grip on Lewis's hand.
Courage seemed to flow from him into her.
"Expecto Patronum!"
This time something leaped from the silver mist.
A fully formed Patronus.
A magnificent eagle.
It streaked through the corridor alongside the wolf, lion, and feathered serpent.
Four Patronuses charged together.
The Dementors broke.
Completely.
The creatures fled into the darkness and disappeared from the train.
The eagle turned around and trotted back toward its owner.
Everyone finally got a good look at it.
"A eagle," Lupin said with admiration.
"A fitting Patronus for Ravenclaw's Head Girl."
Penelope smiled brightly.
She reached out to touch her shining silver eagle.
The moment her fingers approached, it vanished.
"A remarkable Patronus."
Lupin looked at the three students with open approval.
His gaze lingered longest on Lewis.
"Professor?"
Lewis raised an eyebrow.
"Is something wrong?"
"On the contrary."
Lupin smiled.
"For someone your age to cast a Patronus at all is extraordinary."
He paused.
"More importantly…"
"As far as I know, among modern wizards, only one person has ever possessed a magical creature as a Patronus."
"Professor Dumbledore."
"His Patronus is a phoenix."
He studied Lewis carefully.
"You may accomplish great things someday."
"Dumbledore is considered the greatest wizard of our age."
Ciri immediately puffed up with pride.
Even Penelope, who occasionally competed with Lewis, found herself nodding enthusiastically.
At that moment, the Hogwarts Express gave a long whistle.
The train began moving again.
The lights flickered back to life.
"Thank you for saving me."
Penelope squeezed Lewis's hand.
Then, realizing Ciri was standing beside them, she quickly added:
"And thank you too, Ciri."
Still, her eyes kept drifting back toward Lewis.
Something between them felt subtly different now.
"It was nothing," Lewis said awkwardly.
"Your Patronus was amazing."
Penelope shook her head.
"If you hadn't helped me…"
"I never would have succeeded."
Then she straightened her robes and tossed her curls back.
"I still have to patrol the train and calm everyone down."
"So I'll see you later."
With renewed confidence, she marched away.
"She's a good girl," Lupin remarked while watching her leave.
"Very responsible."
"Of course."
Lewis shrugged.
"She's Ravenclaw's Head Girl."
The three of them returned to their compartment.
Inside, Harry had regained consciousness.
Though the cold sweat pouring down his face suggested he still felt terrible.
Ron looked no better.
Curled up beside Harry, he was gripping his friend's arm for dear life.
Hermione sat opposite them, completely overwhelmed by the task of caring for two useless boys.
"Aren't you two feeling better yet?"
Lewis asked.
"Didn't you eat the chocolate?"
He picked up several escaped Chocolate Frogs from the floor and stuffed them into Harry and Ron's hands.
The frogs had been hopping around the compartment the entire time.
Lupin stepped inside briefly.
"It seems you already know how to handle Dementors."
His approving look toward Lewis deepened.
"Unfortunately, I can't stay."
"I need to speak with the driver."
After confirming that Harry and Ron would survive, he left again.
As he passed through the doorway, Lewis could almost hear the unspoken thought lingering in the professor's mind:
This year's Defense Against the Dark Arts class was going to be very interesting indeed.
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