"Expecto Patronum!"
Harry Potter's heart-wrenching cry rang out through the empty corridor. As he shouted, silvery light streamed through the window, illuminating the ancient bricks outside the castle.
Someone looked up and saw the light spilling from the window.
"Expecto Patronum..."
The figure vanished into the shadows.
Though he wanted to see what Harry Potter's Patronus was, he knew it was better not to look.
He turned and disappeared into the Potions storeroom.
Inside the classroom, a silver stag flew from the tip of Harry's wand. It effortlessly drove back the advancing Dementor, forcing it into the wardrobe.
Harry turned in delight and saw a beaming face.
It was Professor Lupin.
Lupin's joy was impossible to fake.
So were the tears glistening in the corners of his eyes.
Professor Lupin applauded, gently wiping the tears from his eyes as he said, "Brilliant, absolutely brilliant, Harry. You haven't disappointed me.
You're the best."
He walked over, crouched down, and gently hugged Harry.
Every movement was extraordinarily tender, as though he were holding a piece of fragile porcelain.
Harry was so overwhelmed he hardly knew what to do. Still, he remembered the training they'd done over the past few days: close the door behind you.
His Patronus had forced the Boggart into the wardrobe. Harry waved his wand and shut the wardrobe door.
The silver stag circled them once before finally fading away.
He hesitated, wanting to hug Professor Lupin back, but before he could, Professor Lupin let go.
Harry felt a little disappointed.
Professor Lupin stood and said, "Go on back, Harry. You've done more than enough. Get a good night's sleep.
For the next week—well, to be precise, starting the day after tomorrow—you probably won't see me.
If you need anything, come find me. But not next Wednesday or Thursday, understood?
If it's urgent, you can go to the headmaster or Professor McGonagall."
Dewey ruffled his hair as he spoke.
Harry was still in a daze. He followed the professor and, without thinking, used magic to bring the wardrobe to the Staff Room. His mind was a muddle the whole way there, giddy with excitement. Just ten minutes earlier, he'd been a little wizard who had run out of strength and magic and nearly fainted. Now, not only had he cast Expecto Patronum, he could still use magic to move a wardrobe. His control over magic had reached a new level.
The change had happened without him noticing.
"All right, thank you, Harry. Thanks for your help."
There were no professors left in the Staff Room. They had things to do in the evenings, too. Dewey asked Harry to take the wardrobe to the far end of the room, then stuck a label on it that read [Boggart, teaching aid]. He waved Harry off.
Harry wandered along, still dazed. As he neared the Hogwarts common room, he saw Hermione carrying a huge stack of books.
Hermione looked so busy she could barely keep her feet on the ground. Harry called her name several times before she finally noticed him.
"What's wrong with you? You seem distracted."
Harry asked her. Hermione looked at him, flustered. "Harry, what are you doing here? It's so late. Shouldn't you be asleep?"
She absently brushed her hair aside, looking even more flustered.
Harry glanced at the time, suspiciously. It was half past nine—not late enough for him to go to bed, and too early for Hermione to be heading back to her dormitory. Seeing Harry's puzzled look, Hermione quickly realized what he was thinking. She put down the books and apologized. "Sorry, Harry. I've just been so busy lately."
"It's fine, don't worry about it," Harry said.
To be honest, both he and Hermione had been so busy lately that they'd neglected their mutual friend Ron. Ron could hardly find either of them these days and was almost angry enough to explode.
Seeing Hermione apologize, Harry didn't think he was any better.
Looking at Harry, tired but still full of determination, Hermione couldn't help asking, "Harry, have you been training with Professor Lupin again?"
"Yes, Hermione!" At that, Harry immediately perked up. He was about to tell her he'd learned the Patronus Charm, but Hermione cut him off, her expression growing even more complicated. "Harry, you should stop being alone with Professor Lupin. Keep your distance."
Harry's eyes widened at her words.
"Why?"
He demanded loudly. Hermione opened and closed her mouth, but in the end, she said nothing.
"I have things to do. I'm leaving."
Hermione lowered her head and hurriedly started to go.
Harry stepped in front of her.
He felt Hermione was hiding something from him.
It might even have something to do with Professor Lupin.
"What's wrong, Hermione?"
He demanded an answer. Hermione's words had clearly crossed one of Harry's lines.
He'd come to see Lupin as a substitute for the affection he'd been missing, so Hermione's words felt like an attack on Professor Lupin.
They'd been good friends for so long.
The way Hermione had spoken, and the expression on her face, gave Harry a bad feeling.
He wanted to know what Hermione knew.
With the Wolfsbane Potion in hand, Dewey entered the box. He took out the potion and thoughtfully poured it down Lupin's throat.
"What is this?"
Lupin asked before drinking it. A week had passed since his last outburst, and he was almost out of anger.
He'd lost his temper with Dewey three times in all, only to realize it was a waste of effort. The man across from him simply didn't care how Lupin treated him. Every time he came downstairs, he'd chatter on and on, saying things that often made Lupin's blood run cold.
Dewey's speech had no logic, no cause or effect. Most of the time, he sat reading books he'd borrowed from the school library. There were plenty of books scattered around his feet, and most of them weren't restricted.
They were ordinary books, the kind students could borrow.
He read them with the focus of a Muggle who'd never read a book before. If he had a question, he'd ask Lupin.
Lupin had lost count of how many times he'd asked what Dewey was trying to do. Dewey never answered. Today was no different.
There was a cup of tea so sweet that just smelling it made Lupin feel phlegm rising in his throat, and a book. Dewey had been there for an hour.
After pouring the Wolfsbane Potion down Lupin's throat, he crossed his legs and read. Once he'd finished the book, he picked up another stack of Daily Prophets. He'd subscribed to the papers so he could learn the things he wanted to know.
He'd paid for the subscription himself.
That made the papers seem especially precious.
Dewey read them carefully, folded several issues he needed, and tucked them into his pocket, ready to leave.
Lupin felt uneasy.
Because today, Dewey was far too normal.
This was so unlike him that Lupin couldn't tell whether Dewey had actually gone mad.
"What are you really up to today?"
Lupin asked before he left. Dewey didn't answer. He raised his wand toward Lupin and smiled. "Good night. I hope you have a pleasant evening, Professor Lupin."
Before Lupin could reply, Stupefy knocked him unconscious.
Dewey went over and picked up a White Card from the floor, his expression saying he'd expected as much.
So Lupin didn't use advanced spells very often either.
Dewey returned to the bedroom and curled up on the floor, arms wrapped around his head like a baby.
Soon, he fell into a nightmare.
A castle, Dementors, and indistinct monsters drifting back and forth.
The nightmare continued, and sweat poured from him.
Dewey opened his eyes wide, his heart racing.
He took a sip of potion and shoved a piece of chocolate into his mouth.
His clothes underneath were already soaked through with sweat. He felt the damp fabric, his expression unchanged.
He was used to it.
He took out the Daily Prophet again and read every line carefully. Then he pulled out the Marauder's Map once more, but still couldn't find Peter Pettigrew.
How interesting.
Dewey's face twisted into a strange, savage expression, gone in an instant. He felt a fire burning inside him. If it didn't die down, he would blow up Hogwarts.
Really blow up Hogwarts.
Even if he was discovered and killed for it, he had to unleash that destruction.
Dewey let out a long breath. He didn't put out the fire inside him. He no longer resisted pain, either.
As long as he could feel that he was still alive.
He wrapped himself in his clothes and lay down on the floor again.
He'd been a professor long enough.
He needed to find a time to let his inner beast run wild.
At the thought, he pointed his wand at himself.
"Avada Kedavra or Stupefy?"
He spoke to himself.
Then he cast Avada Kedavra.
As the Avada Kedavra appeared, he tilted his head aside. The green spell grazed his ear and struck the wall, leaving a small hole.
He looked at the hole and grinned, laughing silently, as if having the time of his life.
When he was done laughing, Dewey dropped his wand and curled up again.
And so the night passed.
Early the next morning, he appeared in the Staff Room, exhausted.
Three professors were there. Snape glanced at the utterly exhausted Lupin and sneered. In his affected drawl, he said, "Oh, Lupin? I thought you'd be lying in bed with the curtains drawn, miserably waiting for this difficult time to pass."
"I'm here to hand things over," Dewey said. "I remember what the students have covered, so, Professor Severus—"
"No, no. You should just lie in bed and wait for the misery to pass. I don't need you."
Severus stood and said, "I won't have you telling me how to teach my students. You mediocre professor."
He said the last word right into Dewey's ear, then turned and left.
Professor Flitwick and Professor Binns looked a little awkward.
Dewey didn't care in the slightest.
He looked at the two professors who remained and said easily, "Well, I'm off to Hogsmeade Village. I'm going to Honeydukes to buy some sweets to reward Harry. Did you know he learned the Patronus Charm in just one week?
"Would you like anything? I can bring it back for you."
The way he bragged about Harry was just like someone boasting about a younger relative he adored—his son, for example.
Professor Flitwick cheered.
Professor Binns also nodded with satisfaction. Harry had learned the Patronus Charm at thirteen. That age didn't make him the greatest prodigy, but it was still impressive.
They were happy for Harry, too.
As Professor Lupin was leaving, Professor Binns thanked him for offering to bring something back. Professor Flitwick did the same.
Dewey smiled casually at them and left Hogwarts.
He wasn't an underage wizard, so he didn't need a guardian's permission to go to Hogsmeade Village.
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