Her you go Anon. Quick and simple, since I've got other things on my table.
Enjoy.
-

Hermione woke up positively bursting with enthusiasm. She almost felt like one of those silly little giggling schoolgirls she held so little respect for.

But how couldn’t she? For Hermione Granger had just had the most fantastic of intellectual experiences. And one which she knew she could follow up and explore further.

Isn’t that something worth getting excited over?

The bushy haired witch threw off her blankets and began to toss on her Gryffindor uniform. As usual her roommates began to grumble, it seemed she was having at least a slightly positive influence. Now they would wake up to complain seemingly on instinct.

“No need!” She offered them. “I won’t be attending classes today.”

“Huh?” Lavender grumbled. “Somebody slipping off for a hot date? Hermione Granger has a life!” She tiredly smiled.

“A date of sorts yes. And definitely hot.” Hermione agreed. “Please at least get yourselves up in time to make second period.” She still felt the need to scold.
With that, and her roommates groans, she left the room.

Now it was time. The experienced witch set to work slipping by teachers, prefects, and what few students were about this early working towards an entirely different location than usual. Not a classroom, nor lecture hall, nor library. No, it was instead one of the little used unremarkable dungeons found underneath the school. Perhaps this particular room held some interest; having a respectable selection of torture implements-all of them quite archaic-surely forgotten from the darker past attached to a great number of the building’s wings.

She actually stepped to just outside the dungeon room and waited in the hallway just around the doorway. After all, it was imperative to not reveal herself early.

Now it was time. The moment to perform the most important part of this fiasco: the Time Turner. Hermione grasped the necklace in her hand and began to turn the hourglass. Eight hours, longer than can safely be done, any lesser witch would end up dead or worse. But Hermione Granger was by no measure a lesser witch.
Naturally as time rolled backwards not much looked to change, owing to the desolate surroundings. However the scholarly little witch knew something would be waiting in there for her: Hermione Granger, of the night before, having retreated down here for some peaceful uninterrupted study time. She stepped around the corner and presented herself.

“Oh!” The completely identical girl exclaimed, looking up from her book. “And why exactly would you be here? We both know it’s forbidden. Minerva warned us.”
Hermione knew she herself wouldn’t be one to waste time on surprise. She wanted the truth. Knowledge.

“You should understand in a moment.” She replied with a smile.

The other self looked confused for a moment then her eyes widened.

“Oh my! This must be some sort of magical preservation law. To ensure two of us can’t co-exist together.” The past self mused.

“My thoughts exactly.” She concurred.

“So you should not be here should you?” Her self questioned.

“True, but it was far too much to resist. As I’m sure you will find out in a moment.”

Hermione tried to put on a seductive voice and pose. Something she was not terribly experienced nor talented at. Still, it more than got the right message across to her past self.

That message being to have no fear of letting loose the urges coursing through her ever since seeing her future self.

“Well then, if I am going to be disposing of you I should get to it shouldn’t I?” The past Hermione smiled.

“I suppose you should.”

“Come on over here then.” She led the current Hermione over to a small stool in front of a simple wooden crossbar. Sitting her down the present Hermione found her shirt being removed, which she quickly helped allow.

“Petrificus Totalus!” Past Hermione shouted the curse.

Granger felt her body instantly freeze solidly in place, rendering her completely and utterly helpless. Which, in this dungeon felt… surprisingly exciting and arousing. Was this simply another consequence of meeting yourself in another time? Does everybody feel this way or did Hermione have tastes of her own influencing this? If so some tastes those would have to be! Or could it be dangerous magic was at play? A curse on her or the Turner perhaps.

It hardly mattered now. With her body rendered helpless and her other self pulling her shoulder forward and lining her chest over the block she couldn’t protest even if she did figure it out. Not to mention how doubtful it is she would anyway.

Hermione turned about and with a few simple wordless waves of her wand a cabinet appeared. Rustling around for only the briefest time she drew out a very crude old hammer and nails of a similar sort.

“An enchantment built into the room. You just need to know the- Oh, of course you’d know that already.” A slight blush crossed her cheeks.

Which was funny. Considering she then placed the tools on the bar and grabbed her bound self’s breast. Carefully seeing if she could flatten it out on the wood.

“We don’t come with much to work with yet do we?” She grumbled. “Whatever. I shall have to make do.”

Grabbing a nail she worked the rather thick old simple bit of iron so it pinched behind a bit of the breast and pushed it down to the wood. Then grasping the hammer in her other hand, she wasted no time bringing it down for a good solid strike. Driving it clean through the breast, albeit making little imprint on the wood.

Granger felt immediate stabbing pain. The terrible crushing impact of the crude blunt nail guaranteed irreparable damage already, and in the most painful way possible. Yet despite that her arousal spiked, seeming to perfectly match her pain. Only her full body bind kept her from producing a most humiliating mixture of screams and moaning.

Hermione meanwhile was grinning like; well, a schoolgirl.

“That felt as good as I expected. Which is far more than it should.”

She wasted no time grabbing another nail and lining it up for the other breast.

*Smack!*

It was actually disconcertingly quiet for both of them. Anyone should be screaming under such treatment, and Granger truly wanted to be doing just that. The most frightening part being that it wasn’t entirely pain that was the reason for that urge. Her cunt felt nearly on fire and she couldn’t move even an inch to touch it.

“Well that was fun. Just one last thing. Flagrante!” Hermione cursed the nail in her left breast inflicting a terrible fiery burn.

“Flagrante!” She followed suite with the right. The heat was almost unbearable.

Agony almost exactly as if her little breasts were on fire; from the inside! Until her past self then dismissed the curse and withdrew the nails. Magically of course.

“This really is fun! In an intellectually stimulating way of course.” Hermione covered up her enthusiasm. “There are precious few ways left to experiment with activities traditionally viewed as ‘inhumane’.”

Granger fleetingly thought of how this would by no stretch of the imagination count as humane. But the crippling sexual haze covering her world drowned that idea out before it could even solidify.

“But I think it’s time to finish.” With a flourish of her wand and this time a few arcane words, the torture equipment in the room changed. Now where a crude rack once stood was a metal frame. A grill of thick metal bars able to comfortably accommodate an ordinary sized human and hold them in place with the manacles on the top and bottom. This frame was also built atop container holding a bed of coals. Lastly, several accessories dangled from the side of said container.

Granger shivered in fear and anticipation.

“Lie down on it. Belly up.” Hermione ordered, dropping the body bind to allow her.

Granger stood up, stumbling at first, and crawled onto the frame lying on her back. Hermione leaned down and browsed the various dangling implements before selecting one and lifting it to show her victim.

“This should help us cook nice and evenly.” It was a thick iron shaft, rather phallic in shape, with something like a clip or slot on the side to allow it to attach to the frame.

“Arvara!” Hermione cast a greasing spell on the shaft. The she lifted Granger’s legs and pushed it against her ass. The wounded girl winced in trepidation, this device was clearly not designed for comfortable insertion. The entire process was made more difficult as the past witch had great trouble forcing it in. But with a great shove the pole forced past her sphincter and rapidly plowed into her rectum.

“Ah!!!” She screamed at the intrusion. It felt painful, but at the same time undeniably sexual being penetrated so deeply.

Hermione attached the shaft to the frame and shackled the dazed witch in.

“Flagrante!” With one final wave of her wand the coals ignited.

Hermione admired her work: a future self bound, rectally penetrated, and beginning to sweat from the heat, but so dazed from the abuse she didn’t even consciously react yet. It was comforting and beautiful really.

The scene only lasted around a minute though, before the bushy haired girl began squirming over the fire. Her motions increased in speed and desperation and load moans began to escape her throat. Clearly however escape was not on her mind.

“You need to cum do you?” Hermione asked with a smirk.

Granger responded with an immediate flurry of nods. “Yessss…” She pitifully moaned.

The past girl offered a condescending sigh. “Merlin do I become a desperate little tramp! Fine, I suppose if I don’t do it for you the next one won’t for me.”

She reached out her wand and simply roughly smacked the girl’s clit and began grinding. Even this rude attempt at help was clearly enough though. As her future self immediately pushed and ground her hips back in response as she sounded joyous cries of release.

“Now hurry up cooking. I need still need to try some for a snack a catch myself some sleep before I can go.” Hermione warned. Adding a hasty spell to stoke the flames.

The warning seemed unnecessary. With her energies spent, and body thoroughly broken, Granger faded fast. Clearly the insertion rod was also doing its part to accelerate the process as well. It wasn’t long before the room smelled of delicious grilling meat, accompanied by the pleasant sound of fat sizzling as it dripped from the holes in the meat’s breasts.

Hermione smiled as she admired it ceasing to be a brilliant witch, or a girl with a future-her future-and instead became a simple meal of roast girl.

As that meat she too would soon escape all the stress and expectations, the cycle of class after class in a mad rush of time travel and grades.

She would just be dinner.