HP: Transmigrating as an Obscurial

Professor Quirrell posed a question:

"Mr. Lovegood, are you familiar with the General Counter-Spell — Finite?"

Vizet furrowed his brow, sifting through the extensive reading he had done since arriving at Hogwarts. Finite... The name rang a bell.

"Yes," he replied after a moment. "There's a universal counter-spell mentioned in The Standard Book of Spells, Grade 2."

A flicker of satisfaction passed over Quirrell's pale face, and for a brief moment, he almost looked pleased.

"Excellent! That is precisely the one," he said, nodding. "Finite is a prime example of a 'counter-spell.' Theoretically, if you master the entire contents of The Standard Book of Spells, this one incantation should be able to dispel every spell within it."

He leaned forward slightly, his voice taking on a smoother, more confident quality than it ever did in front of a full classroom.

"You see, Mr. Lovegood, just as the Unlocking Charm — Alohomora — acts as a skeleton key to unfasten most locks, counter-spells function in much the same way. But as wizards grew more adept at magic, so too did their enchantments become more intricate, more layered."

He tapped the edge of his desk lightly, as if emphasizing his point.

"To counteract that, wizards developed composite magic — spells that don't just rely on a single magical effect, but instead interweave multiple enchantments together, much like..."

Vizet's mind whirred. "Like drawing," he murmured, realization dawning. "If you combine simple shapes — triangles, circles, lines — you can create complex patterns that are far more intricate than the sum of their parts."

Quirrell's lips twitched into something that vaguely resembled a smile.

"A most excellent metaphor, Mr. Lovegood," he praised. "And that, in essence, is how composite spells work. A single curse may be simple. But combine several together, and you create something far greater — and far deadlier."

With a flick of his wand, he summoned a quill and a writing board. The quill hovered in the air, poised to take notes as he began to dictate.

"Now, let us examine the Chronic Sickness Curse. It is an exemplary model of composite magic."

Vizet straightened, readying his own quill.

"This particular spell is constructed from multiple hexes and poison charms, woven together into a single incantation," Quirrell explained, his voice growing hushed, almost reverent. "Ordinary jinxes, when cast separately, have their limits. A single mild hex might cause discomfort, but when layered with a poison curse? It manifests as a chronic ailment, gradually worsening over time."

Vizet listened intently, piecing together the logic behind the spell. The concept fascinated him—the way lesser magics, when bound together, could transcend their individual limitations.

As Quirrell spoke, Vizet found himself reevaluating his initial impression of the man. He isn't just a timid, bumbling professor. His theoretical knowledge was sound—more than that, it was formidable. His explanations were precise, his understanding deep.

Perhaps it wasn't Quirrell's ability that had earned him the disdain of his students, but rather his demeanor. Whatever had happened to him over the summer had clearly changed him — warped him into the nervous wreck he presented in class.

Quirrell suddenly winced, gripping the edge of his desk as though steadying himself.

"Professor?" Vizet asked cautiously. "Are you all right?"

Quirrell exhaled sharply and forced a wan smile.

"Yes, yes, nothing to worry about. Just a... lingering effect of my travels."

He straightened, as if brushing aside his discomfort, and conjured a small scrap of parchment with another flick of his wand.

"That will do for today," he declared. "Now, if you are truly interested in composite magic, I would recommend these."

Vizet took the parchment, scanning the book titles written in a neat, slanted hand:

A Guide to Medieval Witchcraft

The Curious Curses of Eccentric Enchanters

Fighting Fire with Fire: A Study on Hexes

His eyes flicked back up to Quirrell.

"These books are in the Restricted Section," he noted.

"Indeed," Quirrell affirmed. "Without a professor's written permission, Madam Pince will not allow you to access them."

With a flourish, he signed his name at the bottom of the note and handed it back to Vizet.

"Present this to Madam Pince, and she will allow you entry."

Vizet hesitated for just a second before accepting the note, bowing his head slightly in gratitude. "Professor, I appreciate this — truly. I know you gave up your lunch hour for this lesson, and I don't take that lightly."

A strange expression flickered across Quirrell's face — surprise, almost disbelief. His pale cheeks darkened ever so slightly, as though touched with the faintest hint of color.

"I —" he started, then cleared his throat. "A professor's duty is to educate. That is all."

Yet there was something unsteady in his voice, as if the words themselves were foreign to him. He hesitated, then added in an almost tentative voice:

"Do you really believe I taught you well?"

Vizet blinked. "Of course!" he said at once. "Had I come across this material in a book on my own, I doubt I would have understood it so easily. But with your explanations, it made perfect sense. I'd say that's a mark of an excellent teacher."

Quirrell exhaled a breath that almost sounded relieved.

"Very well," he said. "Then, as homework, I have a small task for you."

"Of course — what is it?"

"Summarize the curses we discussed today. Find a way to weave an explanation for them together into a single phrase — one that flows smoothly when spoken aloud. "

Vizet's mind whirred again. "Like the structure of a composite spell?"

Quirrell nodded, his thin lips curling into another small, pleased smile.

"Exactly. If you can do this, it will show me that you truly understand."

"Understood," Vizet said firmly. "I'll have it ready by next time."

Quirrell opened his mouth as if to respond — but suddenly, his whole body tensed. A sharp, pained gasp escaped him, and he turned his back to Vizet almost instantly, his shoulders stiff, fingers gripping the edge of the desk.

"Professor?" Vizet asked, frowning.

Quirrell waved a trembling hand, his voice taut. "You — should go now! Return on Saturday — two o'clock sharp!"

Vizet hesitated, then slowly nodded. "Of course, Professor. Please take care of yourself."

With that, he collected his things and exited the office, shutting the door behind him.

------------------------------

The door clicked shut, leaving the office steeped in silence, save for the sound of Quirrell's labored breathing.

A single tear trickled down his cheek. He wasn't sure if it was from pain or something else — relief, perhaps. Weakness. He couldn't afford either.

Shuddering, he staggered toward the mirror and, with a trembling hand, yanked away the cloth covering the back of his head.

The reflection that stared back at him was not his own.

A pale, snakelike visage leered from the glass, slitted nostrils flaring, eyes gleaming red with amusement and contempt.

"Quirinus..." Voldemort's voice coiled around the room like a whisper of smoke, deceptively soft. "It seems you still haven't learned your place."

Quirrell stiffened as his master's tone shifted into a low, mocking sneer.

"Crying? How touching. Were you moved by the boy's flattery?"

Quirrell swallowed thickly.

"Don't be so naïve!" Voldemort spat, voice curling with disgust. "He praised you because I allowed you to share the knowledge of the Sickness Curse. Without me, you are nothing. Do you understand?"

The words cut deep.

A violent tremor ran through Quirrell's body, his stomach twisting with shame. He hastily wiped his face with the sleeve of his robes and bowed his head.

"Y-yes, Master," he stammered. "I understand."

Voldemort exhaled, a slow, deliberate hiss of satisfaction.

"Good."

Then, his voice sharpened.

"Now — how much have you taught him?"

Quirrell forced himself to steady his breathing before answering.

"I introduced him to the basic principles of composite magic," he reported quickly. "And I showed him the necessary hexes and poison curses."

A beat of silence. Then —

"Hmph." Voldemort's voice dripped with displeasure. "Quirinus... that is not what I instructed you to do. I told you to have him cast the Sickness Curse as soon as possible."

Quirrell winced, the first prickling sensations of pain stirring at the base of his skull. He clenched his fists, forcing himself to speak despite the mounting dread.

"But, Master..." he hesitated, voice strained. "If he casts the spell too soon, the curse could consume him. The effects —"

A terrible, piercing agony erupted through his skull.

Quirrell gasped, his legs giving out beneath him. He collapsed onto his hands and knees, vision swimming as Voldemort's laughter slithered through his mind.

"Concerned, are we?" Voldemort mused, a cruel sort of amusement lacing his words. "Worried the curse might erode him? Tell me, Quirinus — have you forgotten what an Obscurus is?"

Quirrell choked on his own breath.

"He was born a Dark wizard." Voldemort's voice was almost gentle now, which somehow made it worse. "The Obscurus itself is the ultimate curse. I am merely exploring the limits of his potential. Tapping into the unique talent his condition offers."

Quirrell trembled, sweat trickling down his temple.

"Master..." he rasped, forcing the words past his parched throat. "Are you... training him?"

The pain returned in an instant, sharp and punishing.

Voldemort scoffed, his voice now edged with cold disdain. "I do not owe you explanations, Quirinus."

Quirrell let out a strangled cry, his body convulsing under the sheer force of his master's displeasure.

"Your job is to obey." Voldemort continued, his words slicing through Quirrell's skull like a blade. "Now, listen carefully. Continue monitoring Harry Potter. I want to know what sets him apart. And as for the Obscurus..."

Another ripple of pain.

"Do not waste time teaching him theory. You will push him to cast the Sickness Curse — whether he understands it or not. I do not care if it consumes him. I only care if he succeeds."

Quirrell gritted his teeth, nodding frantically through the searing pain.

"Yes — yes, Master!" he gasped.

Voldemort exhaled slowly, the pressure in Quirrell's skull loosening just slightly.

"And one more thing," he added silkily. "Find an opportunity to enter the third-floor corridor again. I need confirmation that the stone is there. You attempted it once on the first night of term — and you failed. Your incompetence disgusts me."

Quirrell clenched his jaw, his forehead pressing against the cold stone floor as he panted for breath.

"I — I understand, Master," he whispered.