Hogwarts, at the entrance of the Great Hall.
The old wizard in gray robes transformed his beard into a fluffy, messy clump. Shoulder-length hair hung down from his temples, all smooth and silvery white. He pulled a silver silk ribbon from his pocket and tied up his beard.
Such hair and beard were a highly deceptive disguise. The old wizard in gray robes stroked his beard and let out a cold snort, feeling slightly irritable. Disguising himself as that heartless brother of his gave him a sense of shame and disdain.
He had arrived at a very opportune time. The lively Easter feast had ended, but the castle lights weren't out yet. Teachers and students had returned to their offices and common rooms, so no one was passing by here.
He walked along the corridor, arriving at the marble staircase landing. On the notice board were the latest announcements:
> Gobstones Club:
> The Gobstones Master Final will be held this Saturday by the shores of the Black Lake.
> Friendly Reminder: Spectators, please bring waterproof cloaks.
> Dueling Club: Holiday sessions cancelled.
> "..."
He had once attended school here too, dropping out after less than two years because his sister needed someone to take care of her. He had heard of these activities before. They seemed exceptionally childish, yet they made him feel a tinge of regret.
It wasn't that he had never encountered these games. Running a tavern, occasionally patrons would drag him into participating. But a barman couldn't play wholeheartedly; he only played along with the customers—that was his duty.
"Headmaster's office, eighth floor..." The wizard in gray robes recited the address silently. Stepping onto the staircase, the quiet steps immediately began to tremble.
"Dammit!"
He froze. Based on his own memories and indirect inquiries from tavern patrons, he had found out the location of the Headmaster's office, but he didn't know the specific details.
This castle was full of magical staircases, turning this way and that, shifting up and down. How was he supposed to get to the eighth floor?
His brain was good, and his memory wasn't bad, but were the patterns of rotation and movement still the same as a hundred years ago?
"No other way. Test it bit by bit, climb up slowly..." The wizard in gray robes clutched his beard tight, resentment rising again toward that brother of his.
"But the caretaker could come up for patrol at any time. Heard he's a Squib named Filch..." The wizard in gray robes thought again. "If I run into the caretaker, I can follow him up to the eighth floor."
...
The Dementors drilled out the window, scattering the gloomy clouds. The cold sea breeze, wrapped in white mist, encircled the entire fortress.
Because it was a special lesson decided on a whim, there was no lesson preparation or plan, only a general knowledge system in mind. When discussing specific details, it was inevitable to think divergently, speaking as thoughts came.
"In the era of classical magic, when magical civilization was just budding, wizards initially divided humans simply into magical and non-magical people—that is, wizards and Muggles."
What Melvin was talking about now counted as common knowledge. Hermione had learned about it before, so both were relatively relaxed, not needing full concentration or note-taking.
"The distinction was also very simple. People with magic could see many magical creatures in nature, like Boggarts and Dementors, which did not exist in the eyes of Muggles."
The Muggle Studies professor didn't teach Muggle knowledge today but focused on analyzing magical creatures instead.
In the nearly half-hour remedial lesson, the emphasis was on the process of magical growth in magical creatures, analyzing the main differences between Dementors and Boggarts. The conjecture that emotional fluctuations promoted magical growth brought great shock to the young witch who was about to enter her fourth year.
The second stage returned to the wizards themselves.
Positive emotions helped students control their magic; a cheerful physical and mental state was beneficial for magical circulation, making learning spells like the Patronus Charm twice as effective with half the effort. Negative emotions subtly influenced a wizard's personality, gradually making people dark and twisted, allowing them to perform Dark Magic with ease.
In the leisure of receiving knowledge, Hermione would occasionally get distracted.
She couldn't help but recall the special lesson. Compared to the optimistic and cheerful Gryffindor and Hufflepuff students, the progress of students from Slytherin and Ravenclaw was slightly slower.
This didn't mean they were Dark Wizards or had dark and evil hearts, just that differences in personality and emotion indeed affected magical learning.
But on the other hand, did this prove that they could show higher talent when learning Dark Magic?
Hermione stole a glance at Professor Levent. If one were to vote on which Hogwarts professor had the deepest attainments in Dark Magic, it would definitely be this young Muggle Studies professor.
Even the former Death Eater, the dark-natured Professor Snape, couldn't compare.
Melvin didn't notice the young witch's distraction; he was gradually delving deeper into the mysteries of magic:
"Before long, scholars discovered that there should be a more detailed classification within the scope of magical people. Children born to some wizard couples could see magical creatures and had weak magical perception, yet could not cast any magic, nor would wands choose them."
"We now call such people Squibs."
...
The wizard in gray robes reached the third floor without hindrance. The staircases seemed to be cooperating with his infiltration. He couldn't help feeling a bit smug, feeling like an unscrupulous goat breaking into his brother's territory.
When he was at the Hog's Head, some old customers who didn't want to show their faces called him "Hog's Head," but he felt he was more like a goat—some breeds could even climb vertical cliffs.
Compared to when he attended school a hundred years ago, the decoration of this campus had changed a lot, but this hardly hindered the wizard in gray robes because the main structure hadn't changed much.
Occasionally, he encountered portraits sleeping late and wandering ghosts. But his disguise was excellent. When those things greeted him, he just nodded slightly and smiled in acknowledgement, muddling through flawlessly.
The wizard in gray robes climbed up to the third floor like this, passing by ghosts and portraits, unable to suppress his smugness.
He felt a secret sense of accomplishment in offending that brother of his.
But this smooth progress soon encountered a problem. The moment he stepped onto the staircase leading to the fourth floor, it suddenly began to rotate, turning from facing the staircase landing to another corridor, ending in a locked room.
He stopped at the junction at the end of the staircase, daring not wander around, worried about getting lost in the complex terrain of the ancient castle.
"Why doesn't Hogsmeade have shops selling maps of Hogwarts!" The wizard in gray robes muttered secretly, inexplicably indignant.
...
The caretaker blew out the kerosene lamp, lightened his footsteps, and stuck close to the wall. Following at his feet, Mrs. Norris raised her tail, listening to the footsteps on the stairs ahead.
The junction of the third and fourth floors of the castle had thickened special walls. The floor in the middle was thicker than other floors. Normal architecture wouldn't be designed like this, but there were two secret passages there.
One was behind the statue of the one-eyed witch, leading directly to the cellar of Honeydukes;
One was the trapdoor in the formerly forbidden corridor, leading to an underground passage. Originally used to house the three-headed dog and store the Philosopher's Stone, it was now temporarily unused, occasionally used for Defense Against the Dark Arts classes.
This was why this secret passage had not been completely sealed to this day, leaving only a copper lock to prevent students from trespassing. It had been peaceful for two years, but now, for the first time, noises were coming from it late at night.
If it were night-wandering little wizards, he would definitely suggest to Dumbledore to hang the students up and whip them!
"Hogwarts should issue a map sent to new students with the acceptance letter... that way maps would circulate outside too..." A murmur came from the landing ahead.
"Why does that voice sound so familiar?" Filch looked down at the excited Mrs. Norris.
A partner accompanying him for more than ten years. Although they didn't speak each other's language, a single glance could convey the meaning of every movement.
At this moment, the long-haired cat's tail was slightly raised, hair standing on end, claws half-extended, rubbing her four paws eagerly—obviously a sign of discovering prey.
And prey during night patrol wasn't rats or cockroaches, only intruders or night-wandering students.
Since Black was caught, there had been no other intruders. Filch licked his lips, twisting them into a grim smile, and carefully poked his head out, suddenly freezing on the spot:
"Headmaster? It's so late, you..."
"!"
Aberforth was also startled inside. His brain spun fast, thinking about what excuse to use to deal with this caretaker.
Filch's subsequent words made Aberforth drop his guard: "Can't sleep again? Before going downstairs to get today's hot cocoa, wanted to take a stroll around the castle for a few laps?"
"Yes, yes..."
Aberforth nodded in admission, his gaze involuntarily moving down, his bright blue eyes seeing the long-haired cat.
Obviously a Kneazle with magical heritage. Raised ordinarily, but magic flowed in the Kneazle's body. Their lifespan was longer than ordinary pet cats, and they were smarter and more alert. Maybe it could serve as a companion to accompany this Squib to the end of his life.
"Hiss..."
Mrs. Norris's cat eyes shone in the corridor. A low growl of unease came from her throat, front paws scratching the ground.
A faint smile curled the corners of Aberforth's mouth hidden by his beard. Very smart cat. It seemed to have sensed he was a fake Headmaster. If its owner were a real wizard, perhaps he could understand its warning.
But Filch was just a Squib. He thought Mrs. Norris was in a bad mood because the hunt had failed.
"Relax, Mrs. Norris..."
Filch tickled the cat's belly with his shoe, trying to comfort the long-haired cat, but it had little effect.
The caretaker didn't mind. He looked up at the Headmaster, a trace of hesitation flashing across his gaunt face: "Headmaster, if we encounter night-wandering students, don't help them escape anymore. These students are getting more and more arrogant. We must catch a typical example to punish and show others."
Aberforth put on an expression of deep thought. He didn't know if that brother of his would agree to this request.
That guy learned lies and deception at his mother's knee. Ambitious and capable, perhaps he would approve of the caretaker's suggestion... but he had feigned the image of a good-natured man for years, and the outside world's impression of him was friendly.
"Last week, that second-year Ravenclaw girl, what's her name, Lovegood or something, came out in the middle of the night looking for some Crumple-Horned Snorkack. If not for you stopping me, Headmaster, she should be scrubbing toilets for a month!"
A second-year little witch, innocent and naive. If Ariana hadn't gotten sick...
The joyful smile of a young girl surfaced in Aberforth's mind. He suddenly lost patience and waved his hand: "Alright, Filch, that matter is over. Don't mention it again."
"Fine... Headmaster, you always spoil them!"
Filch grumbled helplessly. He looked up at the animal portraits on the right side of the wall, seemingly judging something from the arrangement of the animals, and took the initiative to step onto the staircase landing.
Aberforth was slightly startled, thinking he had been exposed, but the trembling stairs under his feet dispelled his doubts.
The two successfully reached the fourth floor. Filch took Mrs. Norris off the platform and nodded politely: "Headmaster, I'll continue my patrol. You go ahead and strol—"
"I wish you a pleasant evening." Aberforth watched his receding figure, feeling very pleased.
...
"I once tried to explain magical talent using the concept of genetics. Not simple dominant or recessive, nor sex chromosome inheritance, but a talent determined by polygenic control and threshold effects working together...
"Muggle couples both carry a small amount of magical genes, but both are below the threshold. The child born from their union happens to exceed the threshold, thus manifesting wizarding talent.
"And children born to wizarding families might fall below the measured threshold, showing only partial magical perception—that is a Squib. If they don't even have magical perception, they are Muggles."
Melvin inevitably touched upon the Muggle field again, but quickly realized this wasn't tonight's theme. He stopped after scratching the surface and quickly pulled back:
"...I might be a heretic in the wizarding world. No one has ever attempted to explain talent with genetics like me. Historically, those who delved into the mysteries of magic rarely dabbled in Muggle science. Our Headmaster, Dumbledore, prefers to explain it with love."
"Love is the most powerful magic in this world."
Hermione showed a thoughtful look. When dealing with Quirrell in the first year, Dumbledore had said something similar.
"Yes. In their philosophy, people who truly love each other have a greater chance of conceiving children with magical talent, while false love is the opposite."
Melvin changed the subject: "But this is more like a beautiful wish. Even parents with false feelings can conceive a powerful wizard like Voldemort."
Hermione looked up, eyes slightly bright. She was very interested in Voldemort's parents.
"This part is innate talent. But after a wizard is born, as an independent individual, memories and emotions become the main factors influencing magic." Melvin didn't elaborate too much.
Hermione wanted to ask, but topics irrelevant to the class could only be left for after class.
"Due to some wonderful opportunities, I have been thinking about some complex topics."
Melvin paused briefly, staring into the young witch's eyes: "Do the souls of Muggles and Squibs also hide a treasure vault of magic? If the door to the vault can be knocked open, can they also transform into wizards?
"Can wizards, like Dementors and Boggarts, open the treasure vault of magic in their own souls by guiding and utilizing the emotions of others?"
Thunder boomed from the North Sea outside the window, as if striking into Hermione's heart. Her mind couldn't help but sway, as if influenced by Dementors.
She involuntarily took a sip of pumpkin juice and said timidly, "Professor, that sounds like Dark Magic."