The chamber was silent—too silent.
The only sound was the flicker of the lanterns on the wall and the soft footsteps of Professor Sinistra as she circled the Mirror of Erised. She didn't seem to notice Hermione's arrival, nor did she detect Harry's quiet presence, hidden beneath layers of cloaking charms.
Harry's heart thudded in his chest.
Sinistra? That made no sense.
He'd expected Quirrell.
In his last life, the bumbling Defense professor had harbored Voldemort beneath his turban. But here—this was different. Sinistra, the Astronomy teacher, known for her distant air and soft-spoken voice, stood before the mirror like a woman possessed.
Hermione hadn't spoken yet. She stood at the threshold of the room, wand clutched tightly in one hand, the other curled into a fist. The tension in the air thickened.
Sinistra tilted her head, eyes locked on the reflection. "It's here. I know it's here."
Hermione stepped forward cautiously. "Professor...?"
Sinistra turned, and her expression twisted into something unrecognizable—something hollow and feverish. "You shouldn't be here."
Hermione's grip on her wand tightened. "Neither should you."
Harry had never seen this side of Sinistra before. She looked gaunt—exhausted and worn—but more than that, her aura was wrong. Not magically. Emotionally. Like something had eaten away at her from the inside.
Sinistra's eyes flicked back to the mirror. "You don't understand. The Stone—it's more than just alchemy. More than immortality."
Hermione stood her ground. "You're trying to steal it."
"No," the professor said, voice trembling. "I'm trying to protect it. From them."
Harry's fingers curled at his sides. Them? What was she talking about? He wanted to step in, to demand answers, but the moment didn't feel right.
Hermione hesitated. "Protect it from who?"
Sinistra's eyes snapped to her again. "You'd never believe me."
With a flick of her wand, she sent a blast of raw force toward Hermione. The younger witch barely had time to cast a shield charm. The spell shattered against it, but the impact sent her staggering back.
That was Harry's cue.
He dropped the invisibility charm and stepped forward, wand raised. "Expelliarmus!"
Sinistra's wand flew from her hand, clattering against the far wall.
She didn't even look surprised.
"Harry Potter," she said slowly, turning to face him. "Of course."
Hermione gasped. "You were here the whole time?"
"Later," Harry muttered. His eyes never left the professor. "What are you doing?"
Sinistra straightened. "What I must. The world doesn't understand what's coming. Dumbledore—he plays with trinkets and riddles while the true enemy watches from beyond the veil."
Harry didn't lower his wand. "You're not making any sense."
Sinistra took a slow step forward. "There are things older than Voldemort. Things darker. The Stone is the only protection we have."
Hermione moved beside Harry. "That's not your decision to make."
"No," Sinistra agreed. "But it's the only one I can make."
She lunged toward the mirror again, this time without her wand. Her hands brushed the glass—and the room pulsed with magic.
The mirror glowed faintly, reacting to her touch. Something inside shimmered, like light refracted through water.
Harry had seen that glow before.
It was what happened when someone almost got the Stone—but didn't.
Sinistra snarled, her voice rising with frustration. "Why won't it give it to me?! I need it!"
Hermione's voice was firm. "Because you want it for yourself."
"No," Sinistra whispered. "I want it to stop them."
Then something changed.
The air grew thick with heat—suffocating. A deep rumble echoed through the stones beneath their feet. Harry felt it in his bones, a sickening vibration that clawed at his nerves.
Hermione stumbled back. "What is that?"
Sinistra gasped, staggering away from the mirror. Her skin had gone pale—almost gray.
"No… I didn't call—no!"
A jagged tear of black light split the space above the mirror.
It wasn't magic. It was something else.
From the wound in reality, a presence seeped through—thick, oily, malevolent. Shadows coalesced into a form. Not human. Not even animal. Just wrong.
Sinistra screamed. "I didn't summon you! I didn't!"
The demon didn't care.
It surged downward—into her.
There was no grand ritual. No ancient chant. Just desperation and a sliver of opportunity.
The room shook violently.
Sinistra's body twisted, her limbs bending at angles they weren't meant to. Her mouth opened in a soundless cry, and then—
She stood still.
Silent.
Transformed.
Her skin had taken on a grayish hue, and her eyes—once human—now glowed with an eerie crimson light. A twisted grin spread across her face as the being inside her adjusted to the mortal shell.
Harry didn't wait.
"Protego Maxima!"
His shield expanded instantly, covering himself and Hermione as the possessed professor raised one hand. Flames licked from her fingertips, searing the floor.
Hermione's breath caught in her throat. "Harry—what is that?!"
He didn't answer.
Because he knew.
It was a demon.
Not Voldemort. Not a Death Eater.
A being from the other side.
The last time Harry had seen something like this, the war had already begun. He remembered the skies splitting apart, cities burning, screams in the night.
Not again.
He raised his wand higher.
"Reducto!"
The spell slammed into the possessed form—but it barely flinched. The demon inside tilted its head mockingly.
Harry didn't flinch. He took a step forward, wand glowing. "You're not staying here."
The demon laughed. "You cannot banish me, child. You don't have the strength."
Harry smiled grimly. "I'm not here to banish."
He muttered a quick incantation—one Hermione had never heard. An invisible force pulsed outward from him, compressing the air. The temperature dropped sharply.
The demon stumbled.
Sinistra's form shuddered.
For a split second, something human flashed in her eyes.
Then a blast of dark energy hurtled toward Harry.
But it never reached him.
A shield exploded in front of him—one not cast by him or Hermione.
Quirrell stepped through the doorway, robes scorched, eyes blazing.
"Get away from them!"
Harry's eyes widened. "You—?"
Quirrell didn't respond. He launched a barrage of spells, faster than Harry remembered anyone casting in the last war.
The demon screamed, lashing out with fury.
And Harry... joined in.
The possessed professor moved like a whisper of death—silent, sudden, wrong.
"Break formation!" Harry shouted.
Too late.
A swipe of her clawed hand shattered Quirrell's barrier with an earsplitting crack, throwing him back against a column. The impact left a red smear.
"Quirrell!"
No time to check. She was on him—snapping tendrils of darkness coiled toward his throat.
Harry ducked, rolled, fired.
"Detonare!"
The blast sent rubble flying, tore the left wing off her humanoid frame. She staggered but didn't scream. Instead, her golden eyes locked onto him with something worse than rage: amusement.
"Oh. You'll make a fine offering."
Harry grit his teeth. He hated the way demons talked. Always acting like the world was already theirs.
Quirrell was coughing behind him, barely upright. "Go for the head. She's not regenerating properly."
"Copy."
Harry sprinted forward, dodging another lash of shadows. His boots skidded across scorched stone. He dipped low, wand in one hand, the other gripping a dagger etched with runes. "Ignis Tempesta!"
A firestorm burst around the demon. For a moment, he lost sight of her.
Then she leapt through the flames, body still burning.
He flinched—too slow—and a claw raked across his chest. Robes tore. Blood sprayed.
He stumbled, gasping, the taste of iron filling his mouth.
She raised her hand for a killing blow.
Then: "Glacies Lancea!"
A spear of ice pierced her leg, anchoring her in place.
Quirrell, eyes bloodshot, stood again, arm outstretched.
"Get up, Potter!"
Harry forced himself to his feet. "I'm up."
The demon screamed, wrenching herself free, the ice melting instantly in the heat radiating from her changing form. Her skin cracked, flaked—horns now visible beneath it. Sinistra's body was losing the battle.
"She's falling apart," Quirel said.
"No. She's becoming herself."
The temperature dropped. The mirror behind them began to hum, and a red tear opened in the air—no bigger than a galleon, but unmistakable.
A hellgate.
Harry's heart stuttered. "No. No, no, no. We're not doing this again."
He sprinted to the altar, chanting sealing runes mid-run, tracing glyphs into the stone with his wand.
Behind him, the demon screamed, "YOU WILL NOT STEAL MY ESCAPE!"
The ground shook.
Quirrell threw spell after spell—chains, fire, blinding light—but each one slowed her less and less.
She reached him.
Harry saw only the shadow before the claw struck.
But Quirrell was there.
He tackled her aside, both of them crashing into the far wall in a blur of magic and muscle. The demon hissed, stunned for a split second—and that was enough.
Harry slammed his wand into the center of the ritual circle.
"Seal. Now."
Blue light erupted beneath his fingers. The gate resisted, whining like something alive. His vision blurred from the pressure, the cost.
But the gate began to close.
"Almost there—"
A rumble.
A roar.
And then Harry felt it.
Like cold fingers wrapped around his brain.
Like being seen.
It looked through the gate. Something deeper. Older. Vast.
The Demon King.
Harry froze.
The gate was barely wide enough to let a voice slip through, but somehow, that presence pushed in like floodwater. Not words—just hunger.
Then the attack came.
A hand. Giant. Ethereal. Pure black, crackling with red lightning. It surged from the gate like a spear of fate, aimed straight at Harry.
His body refused to move.
He'd seen this before. This exact thing. This moment.
Death.
But Quirrell was faster.
"MOVE!" he bellowed—and he did.
Quirrell shoved Harry away, threw up both arms, magic flaring with one last, desperate surge. "INFERNAL BINDING—REJECT!"
The claw struck.
It impaled him.
Straight through.
Harry turned back just in time to see the red lightning explode through Quirrell's back. Blood, burning mana, and shredded robes sprayed the air.
"No—!"
Quirrell's face contorted, but he didn't scream. Instead, he held the claw in place, arms shaking, burning away as raw hellfire seared them off.
With his last strength, he pressed his wand to the ritual circle.
"CLAUDO INFERNUM!"
Light exploded from the altar. The seal activated fully, snapping shut like a trap.
The claw screeched, ripping back through the gate.
And then it was gone.
The gate closed.
Silence.
Harry crawled over, throat raw. "Quirrell—Professor—"
He was slumped against the altar. The hole in his chest still glowed with fading magic.
"Why," Harry croaked, "why would you—"
Quirrell's smile was faint. "You… don't… get second chances. You gave me one."
Harry's hands trembled. "I didn't mean—"
"Shh." A bloody cough. "Protect them. That's all."
His hand fell from Harry's shoulder.
And the light in his eyes faded.
Harry didn't move for a long time.
His chest ached—not from wounds, but from the weight of it. The unfairness. The loss.
And somewhere, deep inside, something cold coiled in his heart. Not guilt. Not even grief.
Resolve.
He looked up.
The Philosopher's Stone still sat untouched on the altar.
The demon's body was twitching its last, steam rising from its corpse.
And Harry Potter—regressor, killer, protector—stood alone in the silence, thinking only one thing.
He wouldn't waste the life Quirrell gave him.
Not again.
The scent of scorched stone lingered, sharp and acrid in Harry's nostrils. Dust danced in the air like ash after a forest fire. Somewhere above, Hogwarts' heartbeat thumped on—oblivious.
But down here, beneath the castle's skin, time had stopped.
Harry knelt beside Quirrell's body.
His robes were still smoldering, his limbs slack, chest unmoving. A hollow gash carved straight through him—still glowing faintly with the remnants of demonic fire. Magic had burned through skin, bone, and soul alike.
Harry's hand hovered over the wound.
He'd seen death before. He'd caused it.
But this was different.
Quirrell had known. He'd known he'd die—and still, he'd shielded him.
"Stupid bastard," Harry muttered, blinking away the heat behind his eyes.
There wasn't supposed to be anyone left like that. Not here. Not in this world.
He ran a shaking hand over his face. The blood had dried at the corner of his mouth. His ribs ached. The slash across his chest pulsed with pain.
He could heal later.
He had to move.
Gently, he pulled Quirrell's cloak over the man's body, covering the wound, the still face, the burnt hands. A part of him whispered that someone should know. That someone should say a few words.
But not now. Not here.
He stood, staggered once, then caught himself.
The Philosopher's Stone still sat on the altar. Untouched. Glimmering faintly in the dim light like an ember refusing to die.
Harry stared at it for a long time.
He could destroy it.
He could take it.
But he did neither.
Instead, he whispered an incantation, sealing it in a containment ward—a bubble of golden light. Just in case someone else came looking.
He turned toward the exit.
The chamber was quiet, but the path back to the surface felt heavier than it should have. Every step echoed too loudly in his ears. His boots left faint red tracks—Quirrell's blood, his own, maybe both.
At the stairway, he stopped.
His eyes burned again.
He hadn't asked for this. Not to fight hell again. Not to lose someone like that again.
But here it was.
Hell, bleeding into this world. Quietly. Subtly. Just like before.
And now, one more life was gone because of it.
He took a breath, held it, then let it go in a slow, trembling exhale.
"I won't let it spread," he muttered to no one.
Then, softer: "I won't waste what you gave me."
He climbed the steps alone.
—
The next morning dawned bright and cold. Too bright.
Classes resumed. The halls bustled. The students gossiped about a rumor—that someone had tried to steal something from Hogwarts, but the staff had stopped it. Dumbledore said nothing. Neither did the professors.
And no one asked why Professor Quirrell was suddenly "on leave."
Harry sat by the lake, away from the castle, legs pulled up, arms resting loosely on his knees. The air smelled like frost. Winter had crept into the bones of the earth.
Footsteps behind him.
He didn't turn.
"Harry?"
Hermione's voice.
He let her approach. She sat beside him without asking, close enough for warmth, but not touching. Silence stretched between them for a while, filled only by the wind rippling across the surface of the lake.
"You've been gone all day," she said softly.
"I know."
"Are you… alright?"
He didn't answer immediately. The word didn't fit. Alright was something you said when things had merely gone wrong. Not when someone had bled out in your arms to stop the world from collapsing.
But she waited. Patient. Present.
He let the silence sit a bit longer, then finally spoke.
"There are things I can't tell you. Not yet."
"I figured," she said.
He blinked, surprised.
She continued, her voice calm. "You're different. You've always been. But you're not cruel. And whatever happened… I trust you."
He looked down at his hands.
They were clean now. But they still felt soaked.
"Thank you," he said, and meant it.
They sat like that a while longer.
Eventually, she got up and left, telling him dinner was in an hour.
He didn't follow.
His mind was still in that chamber. The heat. The light. The weight of Quirrell's body. The pressure of that claw—of his presence.
The Demon King had noticed him. Even through a crack that small, he'd recognized him.
Which meant this wasn't over.
It never really was.
Harry sighed, running a hand through his hair.
Back in the war, he used to believe in second chances. That people could change. That redemption was possible.
Quirrell had proved it.
He'd also paid for it.
That wasn't fair.
But it was real.
And Harry wouldn't let that sacrifice be in vain.
He pulled a notebook from his robe pocket and scribbled a name:
The Stone — hidden under permanent seal. Dumbledore knows.
And below that:
Hell — it's here. Not fully, but enough.
Then, finally:
Prepare. It's coming.
He closed the notebook and stood, glancing once at the horizon.
The lake reflected the sky like a mirror—clear, wide, and deep. Beautiful. But dangerous, too.
He'd keep this world safe.
Even if it meant becoming something he'd sworn never to be again.
-----------------------
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