Who let this Dementor into Hogwarts!

Chapter 247: What should I do if I suspect my roommate is trying to murder me for graduate school admission? Urgent, waiting online.

Voldemort stayed with Nagini, while Cohen returned to the castle alone.

The Dementors outside the castle are still slacking off because Cohen said they can't suck Sirius Black even if they capture him.

Time quickly came to the day when Harry and his friends secretly taught Lupin, with only Cohen and Ron remaining in the common room.

“Harry only learned the Patronus Charm because of Quidditch…” Ron asked Cohen while teasing a lazy salamander, “Why would Hermione learn this—I mean, Professor Lupin said it's not something she should be learning right now—”

The fire lizard spat out a few sparks, instantly igniting the small twig Ron had used to poke its belly.

Fred caught this to amuse Ron—fire salamanders can only survive for six hours after leaving the flames, and wizards usually take their blood when they are about to die.

However, Ron wasn't that cruel; he would release the fire lizard into the fireplace in the common room later.

"I don't understand. Maybe she wanted to murder a Dementor."

Cohen yawned as he lay back in his armchair.

Hopefully, Harry and Hermione won't excitedly show this off in front of me after they learn it...

#If Harry Potter murdered his roommate at Hogwarts, would it allow other Gryffindors to get accepted into graduate school?#
“But it’s good for Hermione to learn this—ouch!” Ron was lightly bitten by the salamander. “It bit me!”

“That means it likes you,” Cohen said with experience. “If it got impatient with you, it would probably burn off your eyebrows instead of biting your finger.”

The fire lizard raised its head and stared at Ron for a few seconds, seemingly wanting Ron to touch it with his hand instead of the burnt, brittle branch.

“Then my hands will be more skilled.” Ron dragged the armchair away from it.

Seeing Ron's boredom, the salamander spat a few sparks at him and then quickly jumped off the table and into the fire.
-
Meanwhile, Harry and Hermione arrived at the place they had arranged to meet Lupin—the History of Magic classroom.

When they first went inside, it was pitch black. Hermione lit a lamp with her wand, and the two waited inside for only five minutes before Lupin arrived with a large cargo box.

“That Boggart from last time,” Lupin said, “was supposed to be killed by my students in my teaching plan—but anyway, it saved me the trouble of finding another one.”

"Can a Boggart mimic a Dementor?" Harry asked somewhat doubtfully. "I mean... I thought it could only mimic a shape..."

“When a Boggart imitates a dark creature, it mimics the corresponding ability's effects to a great extent,” Hermione replied quickly, as if reciting a memorized text. “And the Patronus Charm can also be used to dispel a Boggart.”

“Great answer, Hermione,” Lupin said with a smile. “It’s a pity this isn’t a regular class, otherwise I would definitely give Gryffindor ten points.”

“Alright.” Then, Lupin clapped his hands. “So, let’s begin our lesson now—the spell I’m about to teach—as Hermione said, the Patronus Charm…”

"This is a very advanced form of magic, far beyond the level of ordinary wizards. It's too difficult for junior wizards in terms of their magical power and control, so you should be mentally prepared," Lupin warned.

Harry and Hermione both nodded.

“What can this spell do?” Harry asked.

“It summons a Patronus,” Hermione replied again. “A Patronus is a positive force, an external manifestation of what Dementors rely on for survival—hope, joy, the will to live… But I don’t understand one thing—Professor Lupin, if the Patronus is made up of Dementors’ food, why is it able to stop the Dementors instead of being eaten by them?”

"Because of the non-existent nature of Dementors and their dark, terrifying essence," Lupin said. "First of all, Patronus are the only things that can directly touch and harm Dementors—only non-existent things can attack non-existent things."

“Secondly, the Patronus Charm contains not only joy, but also the wizard’s desire to survive and protect. Its purpose is to fight, not simply to visualize,” Lupin said. “This may be a bit abstract, so I can explain it in a simpler way. The Patronus is a weapon that the wizard uses magic to create, like you fighting with a hard baguette—and now you can only hit the other person with this baguette.”

"Pfft—" Harry chuckled at the analogy. "What would a Patronus be like?"

“Each Patronus is unique to the wizard who created it,” Lupin said. “You need to recite a spell and concentrate all your thoughts on a particularly pleasant moment for the spell to work.”

Harry and Hermione began to reminisce about their happiest memories.

But it's often difficult to judge which memory was "happier".

“The incantation is ‘Touch the Gods, Protect the Spirits,’” Lupin cleared his throat and recited the incantation. “You can try it first.”

Harry managed to summon a cloud of silver smoke on his first attempt—which suddenly reminded him.

“I think I’ve seen Cohen use it!” Harry exclaimed in surprise.

Back in first year, Cohen seemed to have seen him use this spell in the room where the Mirror of Erised was hidden—Cohen also summoned a large cloud of smoke then, but it seemed that Cohen's smoke settled on the ground, while the smoke Harry was summoning was rising upwards…

“Cohen?!” Hermione’s eyes widened.

“Cohen?” Lupin’s expression was strange.

Harry was about to explain, but suddenly felt it wouldn't be good to tell Lupin about his and Cohen's nighttime outing that violated school rules...

“Maybe it was one of those times we tried it in the common room,” Harry corrected. “Cohen seemed to have attracted a bunch of these silvery wisps of smoke too…”

Next up was Hermione's attempt—it took her several tries to summon a puff of smoke, which made her look quite frustrated.

"Is this enough?" Harry asked Lupin eagerly after both of them were able to get a response from the spell.

“You can’t tell its effects just by looking at its form—of course, the final form of the Patronus is a materialized animal, but for you at this stage, there’s no need to be so ambitious,” Lupin explained. “Ready to try it out on a Dementor?”

“Yes.” Harry nodded with great confidence.

But Harry clearly overestimated himself—

After several attempts, he still could not defeat the Dementors disguised as Boggarts with this formless guardian.

"Take care of God! Take care of God—"

Harry repeatedly heard his parents' dying voices, the man's shouts, and the woman's dying screams—death had never been so close to him.

“Perhaps we should call it a night,” Lupin said uneasily after hearing Harry say he heard his parents’ voices. “Facing Dementor training… I shouldn’t have suggested you go through this…”

“How about we leave it at that for tonight, Harry…” Hermione, her eyes welling with tears, said, “It sounds awful…”

“No.” Harry shook his head. “I’m going to try again! I wasn’t thinking about anything pleasant, that’s why…”

Until the very last time, Harry was finally able to stay standing instead of fainting under the Dementors' influence—

“Excellent! Harry, excellent!” Lupin said with satisfaction.

"Can I try again?" Harry asked.

“No more,” Lupin said firmly. “Have some chocolate, Harry. That’s enough practice for one night. Here—”

“Okay…” Harry sat down to watch Hermione practice. “Hermione, this way of practicing is definitely making people uncomfortable,” Lupin said, turning to Hermione. “I’m worried—”

“It’s okay.” Hermione bit her lip. “I have to practice too—I absolutely have to practice.”

Harry didn't quite understand why Hermione was so insistent—she didn't need to be on the field, nor could she offer much help to Harry from the stands, because it was too far away.

Lupin assumed she was doing it for her friend, which reminded him of his own school days with James, Sirius, and Wormtail.

But Cohen, who had sneaked in here in spirit form ten minutes earlier to spy on the teaching session, knew why Hermione was there.

Hermione was afraid that Cohen would hurt her friends because she knew his true identity—no one knew why a creature that feeds on human emotions and souls would infiltrate human society.

If Cohen only had magical beast blood, that would be fine. Even if magical beasts are dangerous, their diet includes other things besides humans.

But Dementors are different—Dementors only harm humans, that's what the book says, and even Cohen himself admits it.

She is currently oscillating between "believing in Cohen" and "being wary of Cohen," and she herself is not even sure what is right.

"Shall we give it a try?" Lupin asked, ready to open the cabinet at any moment. "Ready?"

“Ready…” Hermione nodded.

Lupin opened the cabinet—but instead of Dementors, what emerged was…

“Cohen?” Harry’s eyes widened as he looked at Cohen, who had crawled out of the closet with a chilling expression, then at a bewildered Hermione. “This—”

Boggart, disguised as Cohen, didn't even carry a wand, and his robes were large and tattered—Harry didn't remember Cohen ever dressing so poorly.

"No—no—" Hermione screamed, covering her face, "I can't—"

"Hilarious!" Lupin seemed to understand something and stepped between Hermione and Boggart.

Boggart was turned back into a deflated balloon and puffed his way back into the box.

"What's going on?" Harry asked, full of doubt.

“I’ll handle this,” Lupin said, covering for her. “Harry, why don’t you go back and rest first? I need to talk to Hermione for a bit.”

“Fine… fine then.” Harry said in a muffled voice, seeing that neither Hermione nor Lupin was willing to explain the situation to him.

He is indeed quite tired right now—perhaps Hermione will be willing to explain the reason to them tomorrow.

"Don't—don't tell Ron and Cohen," Hermione warned Harry as he was leaving.

"Huh?" Harry exclaimed in surprise, "What does this have to do with Ron—"

“Just don’t tell them—” Hermione said, “You’ll find out eventually…but not so suddenly…”

The spirit Cohen, who was watching the show from the sidelines, frowned with an imaginary brow.

It's too easy for people to misunderstand and think Hermione has a crush on me!

“Okay.” Harry nodded with some doubt and left the classroom alone.

Now only Lupin and Hermione are left "alive".

"Teach, Professor...?" Hermione asked first when Lupin remained silent.

"You know?" Lu Ping said with a strange expression.

"What do I know?" Hermione tried to hide her suspicions, but Lupin was already pretty sure of his guess.

“You learned the Patronus Charm to protect yourself from a friend, right?” Lupin said.

"You knew about it too?" Hermione asked in surprise. "Or...?"

“Most of the professors knew this, and I even asked Professor Dumbledore after I arrived at the school,” Lupin said. “Professor Dumbledore believed in him—and I believed in him too.”

“I really shouldn’t have doubted my friend…” Hermione said remorsefully, “but the species described in the book… is just too terrifying…”

“Bloodline often doesn’t determine whether a person is good or bad,” Lupin said meaningfully. “However, considering Bogut’s situation, your practice might not be able to continue normally—you should get some rest. You seem to be overworked…”

"Okay." Hermione nodded and hurriedly fled the area.

After Lupin finished packing up the cabinet containing Boggart, he also left the classroom, leaving only Cohen in his spirit form.

He left his body on the dormitory bed, pretending to be asleep, and wasn't in a hurry to go back.

Hermione's self-doubt was actually a relatively important part of Cohen's plan—but she had already learned the spell, and being able to exhale some silver smoke should achieve the same effect...

But what Cohen couldn't understand was that, according to his various plans, Sirius would never be captured by the Ministry of Magic and the Dementors.

There was no foreseeable outcome that "Sirius was captured by the Ministry of Magic".

Under what circumstances will the future that I have observed come true?
However, the time to verify the prophecy is fast approaching—the Hogsmeade holiday the day after tomorrow will be the moment to finalize everything.

Cohen floated back to his body in the dormitory, just in time for Harry to return.

"So, did you learn any new spells?" Ron asked Harry curiously as he returned.

"Will we not have to worry about Dementors next time?" Seamus was also concerned about whether Gryffindor could win the Quidditch championship.

“I know the spell, but the effect doesn’t seem very noticeable,” Harry said uncertainly. “However, I improved a lot tonight, and I’ll practice a few more times. I should be able to practice enough before the Quidditch match…”

"What about Hermione? Has Hermione learned it?" Ron asked.

“She didn’t try—” Harry suddenly remembered Hermione’s reminder.

"Why?" Ron frowned.

“She was...too tired—she had so many classes, she almost fell asleep,” Harry made up an excuse.

“I warned her a long time ago to study less.” Ron shook his head and crawled back into bed. “At this rate, she’ll work herself to death at school…”

Harry glanced one last time at the direction of Cohen's bed, where Cohen was curled up in a ball.

Why did Hermione's Boggart turn into Cohen's appearance?
(End of this chapter)