https://luckyquaffle.com/stories/professor-potter/chapter-9-first-class/
Disclaimer: The characters in this universe start Hogwarts at the age of 15. All characters featured in this story are 18+.
"—and while I understand that my predecessor left under somewhat unusual circumstances, I can assure you that I intend to be here for the full year."
Harry kept his voice level, kept his posture relaxed, even as his eyes swept across the rows of desks and his chest tightened with something he refused to name. Ron Weasley sat near the back with Dean Thomas, alive and whole and laughing at something Dean had muttered, his freckled face split in a grin that Harry had last seen moments before a wall of green fire had swallowed it. Neville was there too, broader in the shoulders than Harry remembered, and Seamus beside him, and every face was a ghost made flesh, every familiar feature a knife sliding between his ribs.
Keep talking. Keep moving.
He let his gaze drift left, toward the Gryffindor side, and found Iris in the second row. She was watching him with that little smile she wore when she was proud of something, her green eyes bright, her red hair tumbling over one shoulder. The sight of her steadied him like a hand on his back. You can do this. You've faced worse.
And then his eyes moved one seat to the right, and his voice nearly failed him.
Hermione Granger sat beside Iris, quill already poised over parchment, her bushy brown hair pulled back in a loose knot that left the graceful line of her neck exposed. She looked up at him with an expression of earnest attention, lips slightly parted, and Harry felt the floor tilt beneath his feet.
She was alive. She was eighteen, and alive, and looking up at him with that bright, eager attention he knew so well, ready to drink in whatever he said next.
But she was also different. The girl in his memory had been slight and angular, brilliant but still growing into herself. The woman before him had filled out. Her white blouse strained across breasts that were fuller than he remembered, the fabric pulling tight with each breath, a soft swell of cleavage threatening at the top button. Same face. Same fierce intelligence burning behind those brown eyes. But wrapped in a body that his treacherous mind immediately began cataloguing in vivid, inappropriate detail.
Stop. She's not your Hermione. She's a student. She's—
"Professor Black?"
Harry blinked. Hermione was looking at him expectantly, her quill hovering above her parchment.
"I was wondering," she said, and even her voice was the same, that slightly breathless quality when she was eager to learn, "if you could tell us a bit about your background? Your approach to Defence?"
She's asking about your credentials while you're thinking about how her tits would feel in your hands. Get a fucking grip.
"Practical experience," Harry said, forcing his voice to remain steady. "I've faced Dark wizards in the field. I know what works and what gets you killed. That's what I'll be teaching you."
He turned toward the board, where PROTEGO was already written in bold letters, and tried very hard not to think about the way Hermione had leaned forward when she'd asked her question, about the gap that had appeared at the top of her blouse, about the soft shadow of cleavage he'd glimpsed before tearing his eyes away.
"The Shield Charm," he said. "Who can show me the wand movement?"
Movement in the front row caught his attention before anyone could answer. Lavender Brown was raising her hand, but that wasn't what made Harry's breath catch. Her blouse was open at the top, two buttons undone, and when she leaned forward over her desk, the fabric fell away to reveal the lacy edge of a pale pink bra and a valley of deep, creamy cleavage that seemed to go on forever.
Fuck.
Harry's cock stirred in his trousers. He shifted his weight, angling his body slightly away from the class, and kept his expression neutral.
"Yes, Miss...?"
"Brown," Lavender said, her voice pitched low and sweet. "Lavender Brown." She smiled at him in a way that made it very clear she wasn't thinking about Shield Charms. "The movement is like this, isn't it?" She raised her wand and made a vague sweeping gesture that was completely wrong, her arm lifting in a way that pulled her blouse even tighter across her chest.
"Not quite," Harry said, his voice slightly strained. "Anyone else?"
"A sharp downward arc, followed by a horizontal sweep to the right."
Hermione's voice cut through the room with crisp precision. Harry looked at her, at the way she was sitting up straighter now, eager to prove herself, and his chest ached with more than lust. She had always been like this. Always the first with the answer, always desperate to be the best.
"Correct," he said, and conjured the movement diagram onto the board with a wave of his wand. "The wand movement channels your intent, but it doesn't create the shield. Your intention does." He stepped out from behind his desk, acutely aware of the way several heads turned to track his movement, the way Lavender's eyes dropped to his trousers before sliding back up to his face. "A shield forms because you mean it to. Because you've decided, in that moment, that nothing is getting through."
He demonstrated, his wand slicing through the air in a perfect arc. A shimmering barrier materialised before him, translucent and faintly golden.
"In a real fight," he said, letting the shield dissipate, "you won't have time to think about wand angles. You'll have a fraction of a second to decide whether you want to live or not."
He began to pace slowly along the front of the room, his eyes moving across the class as he lectured. Hermione was bent over her parchment, quill scratching furiously, and Harry found his gaze drawn to the way her blouse gaped slightly as she wrote. From this angle, he could see the soft swell of her breasts pressing against the white fabric, the shadow of cleavage deepening with each breath. His mind supplied an image unbidden: those breasts freed from their confinement, soft and heavy in his palms, her back arching as he squeezed—
No. Teaching. You're teaching.
He dragged his eyes away, only to find them landing on the Slytherin side of the room, where a girl he recognised as Daphne Greengrass sat with one leg crossed over the other. Her skirt was short, shorter than regulation surely allowed, and where it had ridden up it left a long stretch of pale thigh bare, enough to make Harry's cock twitch against his trousers. Her breasts strained large and full against her shirt, the buttons working hard, and Harry's eyes lingered a beat too long before he wrenched them away.
Merlin's balls.
"The Shield Charm requires total commitment," Harry continued, his voice steady despite the growing problem in his trousers. "Half-hearted intent produces a half-hearted shield. And a half-hearted shield gets you killed."
Lavender leaned forward again, and Harry watched helplessly as her cleavage deepened, her blouse falling open to reveal more of those soft, round breasts pressing together above the lace of her bra. She bit her lower lip, her eyes fixed on his face, and Harry could practically hear what she was thinking. He'd seen that look before. On Iris. On Amelia. On every woman who'd decided she wanted a piece of him.
Focus on the lesson. Ignore the tits. Ignore all the tits.
"Professor Black."
The voice came from the Slytherin side, drawling and familiar. Harry turned to find Draco Malfoy leaning back in his chair, his pale face twisted in a sneer that was almost identical to his father's.
"Yes, Mr Malfoy?"
"I find it interesting," Malfoy said, his tone dripping with false politeness, "that the Board saw fit to hire a professor with no formal qualifications. No NEWT records. No apprenticeship. Just some vague claims about 'field experience.'" He raised an eyebrow. "How do we know you're not simply a charlatan?"
Harry looked at him for a long moment, letting the silence stretch. Then Malfoy's wand came up in a sharp, practised motion, and a jet of red light shot toward Harry's chest.
Harry didn't reach for his wand. He simply raised his left hand, palm out, and the jinx splashed against an invisible barrier and dissipated into nothing. The crack of the blocked spell echoed through the room, followed by a moment of stunned silence.
"That," Harry said, his voice utterly level, "is how you know I'm not a charlatan, Mr Malfoy. You'll find that field experience tends to leave a mark." He lowered his hand. "And as for my qualifications, you might take it up with your father. He was one of the loudest voices arguing I be given the post. I'd hate for him to think you'd embarrassed yourself questioning his judgement."
He let that land before continuing. "Ten points from Slytherin. And if you raise your wand against me again, you'll spend every evening until Christmas scrubbing cauldrons without magic." He smiled, and it wasn't a kind smile. "Do we have an understanding?"
Malfoy's face had gone pale. He nodded jerkily, sinking back into his seat.
Harry let his gaze sweep across the room, watching the way the students were looking at him now. The admiration in their eyes had sharpened into open wanting, enough to make several of the girls shift in their seats, their thighs pressing together. Hermione was staring at him with her lips parted, her quill forgotten in her hand, and Harry caught a glimpse of pink tongue as she wet her lower lip.
This isn't helping.
"On your feet," Harry said, waving his wand. The desks and chairs slid to the edges of the room, clearing the centre. "Pair up. One casts the Shield Charm, the other throws a light Stinging Hex. Then swap."
The students rose and began to sort themselves into pairs, the noise of shuffling feet and murmured conversations filling the room. Harry noted the pairings as they formed: Hermione with Iris, Lavender with Parvati, Ron with Dean, Daphne with a dark-haired Slytherin girl he thought might be Tracey Davis.
He started his circuit near Iris and Hermione, because he was a masochist, apparently.
"Ready when you are, Miss Potter," he said.
Iris raised her wand, her form perfect, and cast without hesitation. "Protego."
The shield that materialised before her was flawless, a shimmering dome of golden light that hummed with power. Hermione's Stinging Hex splashed against it and evaporated harmlessly.
Harry nodded, feeling a swell of pride that he knew he had no right to feel in front of the class. "Well done."
Iris smiled at him, slow and pleased, and Harry moved on before he did something stupid. As he walked away, he felt her eyes on his back, amused and watchful.
He made his way toward Lavender and Parvati, where things were going considerably less well.
"I can't get it to work," Lavender said, her voice pitched high. She turned to look at him as he approached, and Harry watched helplessly as her movement caused her open blouse to shift, revealing even more of that pale, soft cleavage. "Could you show me again, Professor? Maybe, um, guide my arm?"
She's doing this on purpose. She's absolutely doing this on purpose.
Harry should have said no. Should have demonstrated from a safe distance, corrected her form verbally, moved on to the next pair. Instead, he found himself stepping behind her, reaching around to adjust her wand arm, and suddenly his chest was pressed against her back and his nose was full of her perfume and she was pressing her soft arse back against his crotch with a subtle but unmistakable wiggle.
Fuck. Fuck fuck fuck.
"Your elbow needs to be higher," Harry said, his voice slightly strangled. He could feel the heat of her body through their robes, could feel the way she was arching her back to press her arse more firmly against him. His cock was hardening rapidly, straining against his trousers, and if she pressed back any further she was going to feel it.
He looked down, ostensibly to check her form, and found himself with a direct view down the front of her blouse. Her breasts were pale and round and barely contained by that lacy pink bra, the soft flesh swelling above the cups, pressed together into a deep, inviting valley. He could imagine peeling those cups down, could picture those breasts spilling free into his waiting hands—
"Like this?" Lavender breathed, making a half-hearted attempt at the wand movement that involved a lot of hip shifting and very little actual technique.
"You need to focus," Harry said, stepping back before his erection could betray him any further. "Your mind is elsewhere."
Lavender pouted at him, her lower lip jutting out in a way that made him think about what those lips would look like wrapped around his cock, and Harry turned away before he could finish that thought.
As he moved, he caught Iris watching him from across the room. She mimicked Lavender's pout perfectly, batting her eyelashes in exaggerated imitation, and Harry had to stifle a laugh. Brat.
He continued his circuit, passing the Slytherin pair. Daphne Greengrass raised a shield that flickered and gave out, and Tracey's hex caught her across the knuckles, the wand slipping from her stung fingers to clatter on the stone floor.
She bent to retrieve it, and Harry's mouth went dry. Her short skirt rode up as she leaned down, the hem climbing the backs of her thighs to reveal the pale curves of her arse, full and round and barely covered by a scrap of black lace that disappeared between her cheeks. He stood there a moment longer than he had any business standing there, taking in the sight.
Harry's cock throbbed. He could see the outline of her pussy through the thin fabric, could see the way the lace stretched tight across her soft flesh. His mind supplied an image of those panties pulled aside, of his cock sliding between those perfect cheeks, of her moaning as he filled her...
Stop. Stop it. You're a professor.
She straightened, and Harry made himself move on, his erection now a persistent, uncomfortable presence in his trousers that he was having increasing difficulty ignoring. Every time he managed to get it under control, one of the girls would lean or stretch or bite her lip, and it would surge back with renewed enthusiasm.
He completed his circuit and found himself back at Hermione and Iris.
"Your turn, Miss Granger," he said.
Hermione nodded, her expression serious and focused. She raised her wand, took a breath, and cast.
The shield that formed wasn't perfect. It wavered at the edges, thinner than Iris's had been, and for a moment it looked like it might buckle. But Hermione's face set with concentration, and the shield held. Iris's hex splashed against it and dissolved.
"It nearly went," Harry said quietly. "And you held it anyway." He met her eyes, and his voice came out softer than he'd meant it to, softer than he'd given anyone else all hour. "That's the part that keeps you alive, Miss Granger. Well done."
Hermione's face flushed pink, the colour spreading across her cheeks and down her neck. Harry watched it travel, watched it disappear beneath the collar of her blouse, and found himself wondering how far it went. Whether her chest was flushed too. Whether her breasts would be pink and warm if he pulled her blouse open, if he took those soft mounds in his hands and...
She was your best friend. She died for you. And you're thinking about fucking her.
The thought sobered him, and for a moment the grief rose up and threatened to swallow him whole. This wasn't his Hermione. His Hermione was dead, had been dead for four years, her body broken in the rubble of a collapsed corridor while Ron screamed her name. This was someone else, someone who shared her face and her voice and her fierce intelligence but who had never known him, had never fought beside him, had never died in his arms.
And he was standing here thinking about bending her over his desk.
What kind of monster are you?
"Professor Black?"
Harry blinked. Hermione was looking at him with concern, her shield dissipated, her head tilted slightly to one side.
"Sorry," he said, forcing a smile. "Lost in thought. Your technique is excellent, Miss Granger. Keep practising."
The bell rang, and the room erupted into motion. Students gathered their bags, chattered with their partners, streamed toward the door. Harry stood at the front of the room and watched them go, his cock still half-hard in his trousers, his mind a jumble of lust and grief and self-loathing.
Hermione paused at the door, looking back at him with that earnest expression, and Harry felt something twist in his chest. Then she was gone, swept along with the crowd, and Harry was left alone with his thoughts.
Almost alone.
"That was impressive."
Harry turned to find Iris still standing by her desk, her bag slung over one shoulder, watching him with a smile that was warm and proud and just a little bit knowing.
"The wandless block against Malfoy," she continued, stepping closer. "I think half the girls in here soaked their panties."
"Iris," Harry said warningly, but he couldn't keep the corner of his mouth from twitching.
"I'm serious." She stopped in front of his desk, tilting her head to look up at him. "Lavender practically threw herself at you. And Daphne, bending over right in front of you like that?" She laughed. "You're going to be fighting them off all year."
"That's not exactly reassuring."
"It should be." Iris glanced toward the door, toward the corridor where Hermione had disappeared, and something flickered across her face. Satisfaction, maybe. Anticipation. "You know, Hermione is brilliant. Top of our year. She'd probably do anything for some private tutoring."
Harry's throat went dry. "Iris—"
"Just an observation, Daddy." She smiled at him, sweet and innocent and utterly devious, and turned toward the door. "I'll see you later."
She was gone before he could respond, leaving Harry standing alone in his empty classroom, his cock throbbing, his heart aching, and his mind full of thoughts he knew he shouldn't be having.
Private tutoring.
He thought about Hermione's flushed face, her earnest eyes, her breasts straining against her blouse.
He thought about the way she'd looked at him when he praised her shield, like his approval was the only thing in the world that mattered.
He thought about Iris's smile, knowing and pleased, offering him something he hadn't asked for.
Fuck.
Harry sat down heavily in his chair, stared at the empty classroom, and wondered exactly when he'd lost control of his life.