Hermione's Detention (Patreon)

(Disclaimer: Hogwarts starts at 14, making Harry 18 at the time this story takes place.)

Hermione’s Detention

Harry Potter sat in the office of an abandoned classroom, waiting for his girlfriend, Hermione Granger, to show up. He was anxious and excited, spinning a vial of sparkling blue potion between his fingers. Aging potion, a specifically measured dose to make him look thirty-five years old. He had been thinking about this for years. Ever since he had taken an interest in girls, this had been his number one fantasy. Now, finally, he was going to get experience it for real.

A creak from the classroom set his pulse racing and he jerked up from the chair, nearly sending it over backwards.

“Harry?” Hermione called out, her voice echoing slightly in the empty room.

“Be right there.” He called back, his voice on the verge of quivering with nerves.

While he managed to hold his voice steady, he couldn’t do the same with his hands. Carefully, he uncorked the vial with shaking hands, and downed it immediately. He grimaced at the horribly bitter taste as a warmth spread throughout his body. The feeling grew until it was almost unbearable, and his body started growing and stretching in an odd, uncomfortable way. Finally, after several long, horrible seconds, it ended abruptly. He leaned on the desk for a moment to recover, breathing deeply in an attempt to calm his stomach. Standing up straight, he walked unsteadily over to the wall where there was a mirror, left by a teacher long ago. A smile bloomed on his face, or rather, the face that would one day be his, as he stared at his reflection.

Reaching up with one hand, he ran it over the newly grown stubble on his cheek, and adjusted his glasses to better fit his slightly larger face. Looking down at his new, older body, he was happy to see that he would fill out a bit more in the years to come. Things also seemed lower than they should be, though not by too much. At a guess, he thought he had grown about two inches in height. Moving his arms experimentally, his robes felt tight with the movement, thanks to his wider chest and shoulders.

“Harry.” Hermione called out again, this time with a touch of impatience.

“Coming.” He called back, surprised by the deepness of his voice.

Turing away from the mirror, he walked to the door, taking one last, fortifying breath before he pulled it open.

Hermione was sitting sideways at one of the desks, a book open in her lap. She looked up when she heard him enter the room, her eyes widening in surprise as she took in his new look.

“Harry, what-” She started.

“That’s Professor Potter, Ms. Granger.” He said in a stern voice. “You’re late for your detention.”

With a flick of his wand, the door to the classroom locked itself with a loud click and the wall glowed red briefly as the silencing spell took hold.

Turning, he strode over to the teacher's desk at the front of the classroom, and leaned his back up against it, arms crossed over his chest. As he looked back at Hermione, he nearly laughed at the incredulous look she was giving him.

“Harry, we can’t-” She tried to say.

“That’s Professor or sir.” He said loudly over her. “And, if you didn’t want to be in detention, you should have been paying attention in my class, rather than doing your Charms homework. Sexual Education is very important.”

Harry was worried for a moment that she wouldn’t go along with it. For several agonizing seconds she just continued to stare at him. Eventually, she sighed heavily and shook her head, an expression he recognized as her ‘I can’t believe I’m doing this’ look. He couldn’t stop the relieved, excited smile from stretching across his face.

“I’m sorry, sir.” She said, stressing the honorific.

Harry didn’t let her deliberate over acting dampen his enthusiasm, he knew she wasn’t as annoyed with him as she made out to be. In fact, he would bet everything he owned that she had had more than one fantasy about situations very similar to this.

“Come on up here, Ms. Granger.” He said, beckoning her to him.

Hermione put down her book and stood from her seat. Having taken her robes off earlier, she walked up to him wearing just her usual school uniform. A white button up shirt that was stretched across her chest, showing her medium sized breasts nicely, her Gryffindor tie between them, and a pleated black skirt.  Her bushy brown hair had tamed some in the last year, and that, along with her fixed teeth, made her into a strikingly beautiful young woman.

She stopped in front of him, looking up to meet his eyes, and bit her lip nervously. While he was normally a bit taller than her, with his bigger, taller body, it felt like he towered over her. Her thin frame looked even smaller now compared to his broad chest and shoulders. He could see her cheeks turning just slightly pink, a sign of her growing excitement.

“First, I think we’ll see how well you do with the oral exam.” He told her.

Placing his hands on her thin shoulders, he pushed down, leaving no illusion as to what he wanted her to do. Hermione knelt down without protest, and stared at the large bulge in the front of his slacks. With the excitement of fulfilling such a long-held fantasy, he was already rock hard and throbbing with anticipation. He knew he wouldn’t last long.

Undoing his fly, Harry struggled briefly to get his erection to move into a position to get it out. He managed it after a moment, and his long, thick shaft, crowned with a swollen, purple head was pointed directly at her mouth. He wasn’t sure if it was the excitement, the potion, or even just his imagination, but he had never seemed bigger than he did now.

Placing his hands on top of her head, and threading his fingers through her hair, he pulled her forward towards his throbbing cock. Hermione opened her mouth obediently, her full pink lips sliding across the top of the head, and her tongue teasing the underside as he entered her hot, wet mouth. He groaned when her tongue started to circle around what was in her mouth, wetting it with her saliva, and nearly reached a premature end as she looked up at him. Just the image of the strait-laced Hermione Granger looking up at him with the top third of his cock in her mouth, stretching her lips, nearly finished him.

Heroically, he managed to hold back, and began to move his hips back and forth slowly, savoring the feeling. A movement caught his attention, and he realized he wasn’t the only one excited. Hermione had her hands in her lap, one of which had slid up her skirt. Although he couldn’t see what she was doing, the quick, rhythmic motion of her arm left little to the imagination. He wanted to say something, to keep the façade going, but he couldn’t think through the haze of arousal that clouded his mind. All he could manage to do in the moment was thrust the first few inches of his cock in and out of her mouth, fighting the urge to bury himself down her throat over and over until he was finished.

Hermione’s lips stayed closed around his shaft, her tongue lashing him as he pushed in, and sucking hard as he pulled out. While it felt incredible, it was the situation that brought about his swift end. Having Hermione sitting so submissively on her knees while letting him, her professor, use her so willingly, staring into his eyes all the while, it undid him. Grunting, his hands tightened in her hair, and his movements became jerky as he felt his release racing closer.

“Fuck! Swallow it.” Was all he could manage to say.

Euphoria came over him as he pulsed, shooting jets of cum hard into the back of Hermione’s mouth, nearly causing her to gag. She struggled through it, using her tongue to catch the rest as his cock jerked again and again in her mouth. He was surprised at how long and hard he came with so little build up, her mouth nearly overflowing by the end. Breathing heavily, he stood still, remaining in her mouth as his orgasm trailed off, before finally pulling back. Hermione surprised him when she sucked hard on his spent cock, causing him to gasp at the overstimulation. Looking down at her, he could see a playfulness dancing in her eyes as he pulled free, her lips following the contours of his head as it left her mouth.

Leaning against the desk for support, he watched, mesmerized, as she made a show of swallowing what was in her mouth with a loud gulp. With one last deep breath, Harry forced himself back into character.

“Very good Ms. Granger.” He said, trying to act unaffected and knowing he was failing miserably. “Outstanding. Good to see you’ve been studying.”

“Thank you, sir.” She said, sounding on the verge of giggling.

Clearing his throat, he squared his shoulders and regained most of his composure.

“Now, I think it’s time we move on to something else; Anatomy.” He told her.

Extending his hand, he helped her up to her feet and moved her so that she was pinned between him and the teacher’s desk. He quickly pulled off her tie, and worked his way through the buttons of her shirt, leaving her in a plain white bra. Throwing the shirt to the side, he reached up between the cups of her bra, one of her favorites because of its comfort, and undid the clasp. Hermione’s pale, perky breasts bounced as they were released, her pink nipples already hard as she slid the straps off her shoulders. While not as gifted in that area as much as girls like Lavender or Susan, Harry loved her breasts. They were just big enough to full his hands perfectly, as if they were made just for him. Standing out from her chest, they were incredibly perky, with pale pink, puffy areolas, and slightly darker nipples.

Running his hands slowly up her toned stomach, her gently cupped her breasts in his hands from the bottom, running his thumbs in circles around the inside.

“Now, Ms. Granger, what are these called?” He asked in a low voice.

“Breasts.” She said, her breath starting to quicken.

“Very good.” He praised her. “And these?”

Hermione sucked in a breath as he grabbed her nipples between his thumb and forefinger on each hand, gently rolling them.

“Nipples.” She said breathlessly.

“Excellent, now turn around.” He told her.

Hermione turned on the spot until she was facing the desk. Placing a hand between her shoulder blades, Harry pushed down, bending her over the desk until her chest was laying on the wooden surface.

“Stay.” He commanded.

Reaching down, he grabbed the hem of her skirt and lifted it up and laid it over her back, exposing her round, muscular ass, and thick, toned legs. Walking around a massive, stair filled school, with a bag full of books, certainly had its benefits. The only thing left covering her was a pair of grey panties that were clearly damp. Grabbing the sides, her pulled the panties down her legs, exposing the rest of her ass, and her glistening pink lips. As he stood back up, her ran his hands up her calves, and left them resting on her outer thighs.

“And, what is this part of the body called?” He asked.

“Thighs.” She answered quietly.

Gliding across her smooth skin, his hands moved up and in, going from her thighs to her full, round cheeks. He gave them a firm squeeze, watching as his fingers sank into the soft, pale flesh.

“And this?” He asked huskily.

“Bum.” She answered instantly.

Looking up, he saw she had her face turned to the side, eyes closed, and her breathing was getting heavy with anticipation. The smell of her arousal filled his nose as he continued to massage the cheeks of her ass.

“Excellent.” He said lowly. “I think it’s time we moved on to something a bit more advanced.”

Leaving one hand where it was, the other slid slowly over her smooth skin, tracing between her cheeks, and down, coming to rest lightly cupping her hot, tight lips. He could feel his hand getting wet the moment he touched her.

“Well, it seems like you’re enjoying your lesson Ms. Granger.” He said teasingly.

“Yes, professor.” She replied.

“Now, what do we call this?” He asked, sliding his wet hand back and forth slowly.

“M-My vagina.” She said, a quiver in her voice.

“Now, now, Ms. Granger.” He said, continuing to move his hand with a bit more pressure. “No need to be so clinical, this isn’t Biology. Try again.”

“My-My pussy.” She said, almost whispering the word.

Harry’s cock, already back to fully erect, jumped at hearing such a dirty word leave her lips. Sliding his middle finger between her lips, he teased her for a moment, moving it back and forth, before moving his finger to the front and running it over her clit. A long, low moan escaped Hermione’s lips as he teased her.

“Now, without looking, I want you to tell me what this is.” He said.

Grabbing his hard cock by the base, he pushed the head against her lips and started to run it up and down her slit, just as his finger had done moments ago. Hermione let out another moan, this one higher, sounding needy, and she pushed back against him slightly. The head of his cock was drenched in her wetness immediately, nearly dripping with her arousal. Harry had never seen her this excited before.

“Tell me what this is, Ms. Granger.” He ordered.

“Your penis.” She answered.

He tsked and pulled back slightly, the head just barely touching her lips. She whined and tried to push her hips back but his hand, still on her ass, held her in place.

“Again, with such clinical words. Try again.” He told her.

“Your cock!” She nearly shouted.

Harry smiled, loving the sight of his girlfriend in such a needy state. He pushed the head of his cock back against her lips more firmly, and moved it up and down her slit.

“And what do you want me to do with my cock?” He asked.

“Please.” She whined, again trying to push her hips back.

“What do you want me to do?” He repeated, dying to hear her say the words.

“I want you to fuck me!” She begged, nearly yelling.

Harry leaned over her, his cock poised and ready to enter her dripping slit.

“And, what does that make you, Ms. Granger?” He asked in a deep, lustful whisper.

“A slut.” She answered, looking back at him over her shoulder. Her deep brown eyes smoldering in a way he had never seen before.

Any restraint Harry had left broke when she said those words. His hips slammed forward, burying half his length into her tight, hot pussy on the first thrust. Apparently, that was all Hermione needed. With a shriek, she came hard, her walls clamped around his cock, and her legs shook uncontrollably. Her hands clawed at the desk as she squirted around his cock, spraying her legs, his pants, and the floor. Feeling pressure build up around his cock, he pulled out for a moment, watching in fascination a she squirted twice more before she stopped and collapsed into a heaving mess atop the desk.

Giving her no respite, Harry drove his cock straight back into her with another hard thrust, again burying half his length into her. She groaned tiredly as he entered and began to saw his cock in and out, sinking deeper into her pussy each time, until he was buried to the hilt in her incredible heat. With one hand on her shoulder and the other on her hip, he used them as leverage to thrust in and out of her. He started with long strokes, pulling out until only the head was left inside of her, then slamming back in as fast as he could. Hermione’s ass jiggled with each impact, and she grunted cutely every time he bottomed out.

This pace didn’t last long, it wasn’t enough for him. Soon, he was only pulling out halfway before slamming back into her, with a hard, fast tempo. Watching her ass ripple and quiver each time he fully entered her thrilled him. Raising his hand off her hip, he brought it down with a loud smack on her cheek. Hermione let out a loud moan, and her pussy clenched around him as he continued to drive into her. Twice more he raised his hand and smacked her wonderful ass, leaving the pale skin a light pink from the abuse. He could tell from the sounds she made, and the way she pushed back against him harder and harder that she was getting close again, and his end wasn’t far off either.

Grabbing a cheek tightly in each hand, Harry spread her open, exposing her pussy and asshole to his view as he watched his drenched cock spear into her, stretching her tight, pink lips around his girth. He used his grip on her ass to increase his pace, slamming into her without restraint as he chased his end. Hermione tightened around him rhythmically, moaning loudly as she came on his cock for the second time.

The sight of her body shaking, the sound of her moans, and the feel of her walls fluttering around him were what finished him off. Harry groaned and grunted, burying himself as deep into her pussy as possible as his cock throbbed, flooding her with his cum as she continued to shake and spasm around him. With each pulse, his hips flexed forward in a primal urge to go even deeper.

Even as he finished, Hermione’s body remained tense with her climax, her entire body shaking in pleasure under him. Closing his eyes, he savored every twitch, every spasm around his hyper sensitive cock, until, finally, her body relaxed.

Harry collapsed forward of the top of her, his arms supporting most of his weight, as both of them tried to catch their breath. As his breathing finally settled, he bent his head down, and placed soft kisses along her neck and shoulders. With a moan, she tilted her head to give him more room.

“I love you, Hermione.” He whispered into her ear.

“Mmh, love you, too.” She said in an exhausted voice.

Harry smiled affectionately at her and placed a kiss on the side of her mouth that he could reach. He was just about to stand up and move them to a more comfortable position when her voice stopped him.

“Harry?” She called.

“Hm?” He hummed in question, still kissing her neck.

“Do you have any more of that aging potion?” She asked.

“Er, yeah.” He said, surprised at the question. “Fred and George gave me a few vials of it. Why?”

“Well,” she said, her lips quirked up in a playful smile. “I was hoping I could do some extra credit work this weekend, Professor Potter.”