The first day of classes had barely begun, and Theo was already at his limit.

Harry, as usual, was entirely too unbothered about the fact that half the school was currently swooning over him.

Theo?

Theo was not.

Because it wasn't just one or two girls giggling as Harry walked by.

It was entire groups.

In the hallways. In the classrooms. Even in the bloody Great Hall.

Girls fluttering their lashes, whispering behind their hands, sighing dreamily every time Harry so much as existed.

And worst of all?

Harry was barely noticing.

Theo, walking beside him, noticed everything.

The shy glances. The way some girls faked reasons to talk to Harry—asking for directions they didn't need, pretending to drop things in front of him, giggling at things that weren't funny.

And Harry?

Harry was just smirking through all of it, mildly amused at best.

Theo was going to hex someone.

Blaise, watching Theo's patience rapidly decline, chuckled from behind them.

"Oh, this is entertaining," Blaise murmured.

Pansy, walking alongside him, smirked. "I give it two days before Theo loses it completely."

Theo ignored them.

Instead, he exhaled sharply as yet another group of girls giggled when Harry walked past.

Harry, finally noticing Theo's unimpressed expression, snorted.

"What's the matter, Theo?" he teased. "Jealous?"

Theo stopped walking.

Turned.

Stared at him.

Then, in one fluid motion, Theo grabbed Harry's tie, tugging him just close enough to lean in and murmur—

"You have no idea."

Harry's breath hitched.

Pansy choked back a laugh.

Blaise whistled. "Oh, well done, Nott."

Harry, for once, was speechless.

Theo, smirking, patted his tie and walked ahead.

Harry, blinking rapidly, muttered, "I hate him."

Pansy grinned. "You love him."

Harry groaned.

Slytherin House was in amused giggles the rest of the way to class.

Professor Lockhart: A Walking Embarrassment

By the time they reached Defense Against the Dark Arts, Harry had finally recovered from Theo's antics.

But nothing could have prepared him for Lockhart.

The moment the man burst into the classroom, flashing a bright, toothy grin, Harry had to physically stop himself from groaning aloud.

Lockhart strode to the front, his obnoxious peacock-blue robes shimmering, and spread his arms wide.

"Welcome, welcome!" he announced grandly. "To another fascinating year at Hogwarts! And—" he turned to the class, beaming, "—to what will undoubtedly be your most exciting Defense Against the Dark Arts lessons yet!"

Harry blinked.

Theo exhaled sharply.

Blaise was already grinning.

Pansy, whispering, muttered, "This is going to be horrible."

Lockhart continued.

"Now, now, I know what you're all thinking!" He flashed his too-white teeth. "How fortunate you all are to have the one and only Gilderoy Lockhart as your professor—"

Harry sighed loudly.

Lockhart's eyes snapped to him.

"Ah! Harry Potter!" he exclaimed.

Harry immediately regretted breathing.

Lockhart strode toward him, ignoring the way Theo visibly tensed beside Harry.

Lockhart placed a dramatic hand over his chest. "I must say, my dear boy, it is an honor to teach you! Why, when I was your age, I too was a natural at Defense! Perhaps you'll follow in my footsteps, eh?" He winked.

Harry, done with this entire conversation, tilted his head.

"Oh?" he murmured, smirking. "You mean I'll grow up to be a fraud too?"

Silence.

Then—

Blaise cackled.

Pansy covered her mouth, shaking.

Theo grinned darkly.

Lockhart, face twitching slightly, laughed too loudly. "Oh, Harry, you do have a sense of humor!"

Harry smirked. "Oh, I wasn't joking."

More laughter.

Lockhart cleared his throat loudly, straightening his robes. "Well, humor aside, let's get started, shall we?"

Harry sighed.

This was going to be a long year.

The Hissing in the Walls

It was late by the time Harry left the Slytherin common room, making his way to the kitchens.

Theo had offered to come with him—offered being a polite way of saying Theo had demanded—but Harry had waved him off.

It was just a quick trip.

Nothing to worry about.

Or so he thought.

As he passed through the dimly lit corridors, the castle eerily silent at this hour, something stopped him.

A sound.

A whisper.

A hiss.

Harry froze.

His heart slammed against his ribs, and for a moment, he thought he was imagining it.

But no.

It was real.

Soft, slithering hissing, curling through the air like a breath of wind through stone.

"Where… issss my Massster…?"

Harry's blood ran cold.

The voice was thin. Ancient. Searching.

The walls whispered, shifting with something restless.

"Massster… where…?"

Harry's fingers twitched at his side.

Because the worst part?

It wasn't just a voice.

It was calling for him.

The air in the corridor shifted.

The hissing wasn't just a sound—it was a presence, winding through the stones, curling through the cracks of Hogwarts itself like a living thing.

"Massster… where…?"

Harry's breath hitched.

Because he understood it.

Perfectly.

Not in the way someone translates a foreign language—but as if it had always been part of him.

Natural. Familiar.

Something deep in his blood stirred, waking from centuries of slumber.

His pulse hammered. His fingers itched to reach out, to answer, to command.

He swallowed hard.

No.

Not here. Not now.

With deliberate control, he exhaled slowly, shaking off the eerie weight settling in his bones.

Whatever was speaking to him?

It was looking for him.

And something told him—

It wouldn't stop until it found him.

Slytherin Knows Everything

By the time Harry returned to the Slytherin common room, his mind was still buzzing.

The fire crackled warmly in the emerald-lit space, casting shadows against the stone walls, but Harry barely noticed.

Because Theo was waiting.

And Theo noticed everything.

"You're late," Theo muttered, lounging on the couch, watching him with sharp, knowing eyes.

Harry sighed, dropping into the seat beside him. "I was gone for twenty minutes."

Theo tilted his head, studying him. "You look tense."

Blaise, stretched out in the opposite chair, raised an eyebrow. "What did you do?"

Pansy, filing her nails, smirked. "Who did you traumatize?"

Harry exhaled sharply. "I didn't do anything."

Theo's gaze flickered over him, his fingers twitching at his side like he was resisting the urge to pull him closer.

Harry sighed.

No use hiding things from them.

"…I heard something."

Silence.

Then—

Blaise hummed. "Define something."

Harry hesitated.

Then, quietly—"Hissing."

Pansy's hand froze mid-motion.

Blaise blinked. "Hissing?"

Theo's expression darkened. "Parseltongue?"

Harry nodded. "Yeah."

The flames in the fireplace crackled loudly.

Slytherin House was many things—ruthless, cunning, calculating—but most importantly?

They were observant.

And right now, every single one of them was listening.

Theo, voice low, asked, "Where?"

Harry sighed, rubbing his temple. "The corridors. It was… searching. Calling for someone."

Theo's jaw clenched. "Not someone." His dark eyes locked onto Harry's.

"You."

Harry swallowed.

Because he knew that.

Knew it the moment he heard the call.

Knew it the moment something inside him responded.

Blaise, ever the one to ease the tension, chuckled darkly. "Well. That's concerning."

Pansy snorted. "Just another day in the life of Harry Bloody Potter."

Theo wasn't laughing.

Instead, he leaned forward, his voice dangerously calm.

"If something is looking for you," he murmured, "then we need to figure out what it is."

Harry exhaled slowly. "Yeah."

And deep down, something in him already knew the answer.

This wasn't just a voice in the dark.

This was the legacy of Slytherin himself.

And whether he liked it or not?

It was waking up.