In the center of the isolated island constructed by the Room of Requirement, at the entrance of the fortress prison, Melvin led the way through the open stone gates.
There were dried bloodstains in front of the stone gates. Hermione, clutching the languid water snake, paused briefly to look at them before hurrying to catch up.
The kerosene lamps and torches hanging on the walls burned silently. Only the footsteps of the two echoed within the fortress.
"The Room of Requirement can satisfy the requests of multiple teachers and students simultaneously. In different scenes and rooms, the requirements of both parties do not interfere with each other. As long as the person who enters the room first does not make an exclusive request, it is no problem for others to enter later."
Melvin introduced as he walked, "You should pay attention when you come here in the future. Professor Trelawney sometimes hides empty sherry bottles here. Her request at that time would be 'a room that only I know about' or 'a room that cannot be found by others.' The Room of Requirement might not respond to you, or the door might appear but can only be opened from the inside."
"A hidden room to hide empty bottles?"
Hermione didn't know what to say. "Besides Professor Trelawney, who else knows about this place?"
"Headmaster Dumbledore. According to his story, he had an urgent need to use the bathroom one night and stumbled upon a room full of chamber pots." Melvin casually exposed the Headmaster's embarrassing story, not caring about Dumbledore's dignity at all.
The young witch following beside him laughed, the tension she felt outside the fortress fading. "The Headmaster must be talking nonsense."
"I think so too. Given the Headmaster's personality, he must have examined it carefully. He probably even counted how many bricks are on the wall."
Melvin continued his introduction: "There's also Professor McGonagall. Last time when Severus was hunting Sirius down and the situation was critical, I let Sirius hide here for a night."
Hermione nodded. As she followed the professor into an office, she suddenly remembered something. If Sirius hid here, what did it have to do with Professor McGonagall? How would she know?
Before she could stop walking, her suspicious look had already betrayed her question.
Melvin noticed his slip of the tongue and shrugged. "Because Dumbledore and she were hiding around the corner peeking at the time."
Many memories flashed through Hermione's mind. No wonder the professors' reactions were overly calm when Sirius broke into Hogwarts—even abnormal. It seemed only Snape and Professor Lupin were kept in the dark, anxious and struggling because of it.
She had many questions she wanted to ask, but that matter had passed, and she was here for a remedial lesson today. So she shook her head and followed the professor into the room.
On the periphery of Azkaban prison, the room to the right of the first-floor entrance hall was the Aurors' break room. There was a square observation window on the wall. Here, there was a fireplace for transport, a dining table for tea breaks, and outdated newspapers.
The Room of Requirement couldn't produce real tea and pastries, but Melvin had them in his pocket. In a short while, silk-like flames rose in the fireplace, the teapot emitted the sweet scent of pumpkin juice, and cookies and shortbread were arranged on a plate.
Yurm was no longer listless either. It asked for a cup of pumpkin juice for itself, extending its tender tongue to taste it sip by sip.
"There are no Aurors and no prisoners. The Dementors outside are fake too. It just simulates the buildings and terrain on the island."
Hermione took a sip of pumpkin juice and looked around curiously. "Last term, I read your investigation paper on Azkaban, Professor. Are we going to do something here?"
"Some things being fake doesn't mean everything is fake."
Sitting in the chair opposite, Melvin smiled. The suitcase he had been carrying all the way was placed at his feet. "For example, the Dementors in the thick fog."
Hermione's gaze moved down, a vague guess forming in her heart, her throat tightening. "The Dementors from the night of the Patronus Charm special lesson?"
Seeming to sense the gaze of the two wizards, the suitcase that had been trembling occasionally outside quieted down. On the side of the suitcase, only the alchemical array constructed from Ancient Runes remained, blinding silver light flashing. Delicate magic maintained the Undetectable Extension Charm, sealing the evil and ominous dark creatures inside.
Suddenly, the flowing light on the array extinguished, and the suitcase began to tremble again.
The latches on both sides popped open with a click. A wave of impact erupted from inside the case. The lid threw open, and a dense group of black shadows rushed out.
Freezing, bone-chilling fog filled the room like a blizzard. The shadows of cloaks floated in the thick fog, their pale, scabby hands flickering with a faint glow.
Nearly a hundred Dementors. The vast majority rushed straight out the window to roam freely in the sky, while one or two foolish ones remained in the room, staring eagerly at the two wizards.
Black cloaks hung behind them, their bodies floating in the air like Inferi draped in black robes.
Having not eaten for months, their eyes were practically glowing green.
Hoo...
Obvious inhaling sounds came from their throats, as if they wanted to suck the air in the room dry.
"Expecto Patronum!"
The young witch took a deep breath and waved her wand lightly, summoning a round, cute silver otter.
The Patronus swam around the room, curbing the magic released by the Dementors. But the suddenly dropped temperature still made Hermione shiver. "Professor, I've already mastered the Patronus Charm. I don't need special teaching."
"Dementors serve as special teaching aids, not just for practicing the Patronus Charm."
Melvin whispered. The scattered silver light fell on the ground like cold moonlight.
Melvin's fingertips moved, directing the silver light to form beams of flowing light, agile and light, like water snakes swimming in a cold pool. This was an extended technique of the Patronus Charm, retaining the outline of the corporeal Patronus in exchange for numerical superiority.
Melvin's index finger swayed gently, directing them like an African priest charming venomous snakes with a flute.
Beam after beam of light wrapped around the Dementors, pinning their limbs, locking their stiff joints, and trapping them firmly in mid-air, motionless.
"Since the last special duel lesson, I've kept these Dementors in the suitcase, checking their status and counting them regularly," Melvin said.
"Back in Muggle school, the science teacher would also ask us to observe animals and write journals."
Hermione stood up and approached, holding her breath involuntarily. She had never observed a Dementor this closely. Remembering Harry's encounter, she was slightly nervous. "Mom got me a frog to raise, feeding it mealworms regularly, but it died later... The last few pages of the observation journal were dissection experiments. The teacher refused to give me an 'Outstanding'."
Hollow eye sockets with flickering dim light floating inside, devoid of any living emotion.
Hideous mouthparts, breathing faintly as if devouring something invisible.
From a distance, it looked like a skeleton frame, similar to the skeletal specimens in medical schools. But up close, one realized that Dementors had flesh and skin. Not the fragile flesh in formalin solution that broke at a touch, but with signs of decay yet clear texture, like tanned leather.
"If Dementors don't eat for a long time, will they die?" Hermione turned back to ask.
Since the discovery of Azkaban in the 15th century, the Ministry of Magic had forbidden anyone from studying or raising Dementors. The Department for the Regulation and Control of Magical Creatures classified Dementors as dangerous beasts, and the Department of Mysteries regarded Dementors as taboo creations of Dark Magic. There was very little information about Dementors in the entire wizarding world.
Privately raising Dementors like Melvin—he might be the first wizard since Ekrizdis, the creator of Azkaban.
"A question that hits the key point directly. If this were a class, I'd give you points."
Melvin looked at the dark creatures confined in mid-air. "For a long time, the wizarding world has believed that Dementors are existences similar to ghosts. They share many commonalities: difficult to affect with magic, physical proximity brings a chill that touches the soul. Likewise, many scholars believe that Dementors, like ghosts, are nearly immortal."
"But?"
"But they are wrong. Dementors will wither and die, and after death, no corpse remains."
Melvin said softly. The cold fog escaping from the suitcase gradually faded and disappeared in a flash. "A total of 97 Dementors were captured on the night of the special lesson. Now only 89 remain, but no bones were left behind."
"Wither and die... like plants?"
Hermione noticed the professor's specific word choice, her eyes brightening slightly. "They are born from thick fog, and after death, they dissipate into the thick fog, turning into nutrients to nourish their kind like plants?"
Melvin nodded slightly. "That thick fog isn't tiny water droplets condensed from water vapor, but more like a product of condensed special magic, lingering around the Dementors. When the Dementor population absorbs enough happy memories and has sufficient magic, more Dementors are born in the fog."
"And when the Dementor population lacks food for a long time, some Dementors dissipate, turning into thick fog to nourish their kin?"
Hermione quickly understood, drawing inferences. "So the number of Dementors in Azkaban always remains constant, because the food the prisoners there can provide is limited, only enough to maintain the daily activities of the Dementor population."
She spoke briskly: "And during the Wizarding War, the Dementor population followed Voldemort, plundering everywhere with the Death Eaters, causing their numbers to grow significantly. After the Wizarding War ended, they returned to stability."
"Yes, their reproduction method is similar to the self-regulation of plants."
Melvin nodded and smiled. Teaching a good student was simple. "I'm looking for a more harmless and reasonable way to raise Dementors, trying not to cause physical and mental damage to humans while satisfying these guys' appetites... With food as a reward and the Patronus Charm as punishment, maybe I can really teach them ballet."
Hermione knew he was referring to the story of Barnabas, but tonight's lesson was too shocking, leaving her unsure how to respond.
She was silent for a moment, frowning with some conflict. "Professor, raising Dementors without authorization... the Ministry won't allow it."
"Wait until you become the Minister for Magic to say that."
Melvin waved his hand. "Back to the topic. Today's remedial lesson is not Care of Magical Creatures, nor Defense Against the Dark Arts, but Charms. Showing you Dementors is to help you understand the essence of magic."
"The... essence of magic?"
"For example, when you and Harry started remedial lessons two years ago, you practiced dueling under my supervision. Because you mastered more spells and read more materials related to combat, you often had the upper hand in practice." Melvin looked at the young witch.
"..." Hermione nodded blankly.
"In the two years since, you've had mutual wins and losses, but Harry has gradually revealed his talent in dueling. His reactions are faster, and he can follow his instincts to make the right choices in combat, so he often has the advantage." Melvin deliberately slowed down his speech to guide the student's thinking.
Hermione recalled the dueling practice over the past two years and nodded. "He is a Quidditch Seeker. His athletic talent translates into dueling. His Disarming Charm is powerful, and his magical power grows very fast, but..."
Hermione frowned slightly, showing an expression of thoughtful recollection. "At the beginning of last term, I could always suppress him in combat."
The reason for Harry's rapid growth in magical power was complicated. Aside from talent and the ancient magic flowing in his blood, it was also because an old devil was hiding in the scar on his forehead.
Melvin didn't focus on Harry; his target was Hermione. "Because you had just returned from Paris last summer. You met Bastian, encountered a major change, and experienced intense emotional fluctuations."
"But what does this have to do with Dementors?" Hermione looked blank.
"Emotions. Emotions are the key to opening the treasure vault of magic." Melvin guided patiently.
Huff huff sounds came from behind. Hermione turned around and watched the Dementor panting heavily. The Patronus light on its body was bright, twisting like a snake, obliterating the cold fog lingering on the black robe.
Hermione's eyes widened. Many things flashed through her mind, but she couldn't connect them.
"The existence of Dementors and Boggarts is very peculiar. Without souls, the treasure vault of magic is hidden in their bodies. If emotions are the key to opening the treasure vault of magic, they themselves do not possess the ability to generate emotions. Happiness, fear, nothing... they can only feed on human emotions.
"Boggarts feed on fear more conveniently; it can be directly mapped onto themselves. The more terrified the wizard, the more terrible the thing it transforms into, possessing the true magic of the illusion to some extent.
"Dementors are social animals. The more happy emotions they feed on, the magical growth makes the cold fog denser, birthing more kin and strengthening the group.
"A wizard's treasure vault of magic is hidden in the soul. Ordinary wizards can only increase it slowly with age. But when encountering life changes, intense emotional fluctuations make the soul tremble. The door of the vault reveals a crack, and magic flows along the crack into the wizard's body."
Melvin paused. In a sense, Voldemort making Horcruxes was taking a shortcut—directly tearing the soul, knocking open the door of the vault, letting magic pour out directly for rapid growth.
Becoming the most powerful Dark Wizard in history in a short time.
The Dementor's panting echoed in Hermione's ears. She actually felt she could hear the sound of magic flowing out along the crack—faint, slow, and unceasing.
"Emotions are divided into different categories. Positive love and happiness, negative fear and hatred. Many wizards have already touched upon this field. Different emotions have different effects on magic."
Melvin's fingers swayed, relaxing the restraint on the Dementor. "Positive emotions are conducive to wizards mastering defensive magic, like the Patronus Charm. Dark negative emotions are more suitable for Dark Magic, Unforgivable Curses, and the like.
"Your Headmaster always chatters about the magic of love being beyond imagination, but in my opinion, the magic of any emotion exerted to the extreme is powerful. This involves some knowledge of psychology."
Hermione wanted to find paper and pen to write it down, but Melvin changed the subject: "If you are interested, you can learn about it when you go home for the holidays."
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