Walking self-consciously into the library, incredibly aware of her panties sticking to her, Hermione quickly located the book and found a table in a deserted corner. Flicking through the pages covered in diagrams, spells, and incantations. Already horny at all of the incredibly graphic depictions of various acts, she tried to focus and find the spell she had used on Harry. Eventually, she found the page and began reading.

The spell turned out to be functioning exactly as intended: to give two partners the experience of each other's orgasms. Unfortunately, and much to her surprise, she had read the footnotes properly. The spell had been created as an experiment by a group of scholarly, monastic witches - and as a result had never been tested on men. Hence the slight mix up. And if that wasn't bad enough, the only way to break the spell was to make each other orgasm at the same time. Well obviously they couldn't do that.

Her mind racing, she sat back in her chair. How had she missed this? Was she really so horny and desperate that she'd forgotten how to read? It could be fun though, right? There were loads of spells and diagrams in the book about how to make men and women orgasm, maybe she could try some with Harry? Flicking idly now back through the book, she reached her hand down the front of her skirt and underwear - moving gently over her wet, sticky pussy. This would get Harry back for making her cum in the toilet earlier. Glancing around the room and blushing, she turned her attention to the tome on the desk. She found all sorts of things in the pages: bodies entwined, men touching each other's cocks, women rubbing magically-enlarged clitorises against each other, spells for conjuring magic dildos and having sex with them. Hermione zoned out of reality as she felt her cum-soaked fingers rub over her clit - oblivious to the people walking towards her.

"Hello, Hermione!" Luna called over. Startled, Hermione quickly pulled out of her skirt, wiped her hand on the inside of her cloak, and slammed the book shut.

"Oh, uh, hi, hello Luna, Cho!" She stammered, caught completely off-guard by the two Ravenclaw girls.

"What're you reading?" Luna asked.

"Oh, nothing much, nothing- nothing interesting. Advanced spells."

"Looks fascinating." A knowing smile crossed her face.

"It was, actually. What are you guys doing here?"

"I'm struggling with something, so Luna's helping me find a book." Said Cho.

"Anything I can help with?"

"Um, I don't think so. I'll just look for a book."

"No, uh... worries... aahh..." Hermione gasped as she felt her clit throb against her will. Harry was masturbating... again!

"Are you okay?"

"Yeah, um, fine. Just need to put this back and I should probably get going. It's late." She picked up the book, and glanced at the glorious summer's day beyond the window.

"Oh, alright. Don't let us put you off!"

"No, it's not you, its... I need to go." She placed the book back on a random shelf, something she would have to forgive herself for - but she really didn't want to risk ejaculating all over the floor in front of her two friends. Quickly gathering her things and exiting the library, she almost ran as the continuous stimulation on her clit caused her to dribble from her pussy.

Worried she might cum, she turned down a narrow, empty corridor and tried to hide herself behind a column. There, she placed her bag on the floor, crouched down with her back against the wall, and pulled her sodden panties aside to reveal her glistening, hairy pussy to the world. Holding her skirt out of the way, she took deep breaths as she neared orgasm, looking down at the floor to see thin white precum puddling beneath her. The throbbing reached a new, vigorous tempo and she could hold back no longer: climax bubbled over her, she made sure to keep her eyes fixed on her pussy as she came. Her hips and tummy trembled and quivered as her vagina contracted and gushed thick ribbons of cum in front of her. Long, thick strands shot out almost a foot in front of her - her shaking making it hard to aim, sending her seed flying in all directions. Quickly strumming her hand over her clit, she sent fresh waves of intensity shooting up her body, causing the last drops of cum to pour out of her - and her pussy relaxed one last time, until she could cum no more.

Slowing her fingering as she calmed down, she reentered the real world, and immediately flushed bright red, embarrassed by her predicament. Here she was, propped up against the wall of a public corridor, her pussy fully on display, and thick puddles of semen all around her. Standing back up, she pulled her panties back over herself, and picked her bag up. Realising her fingers were still covered, she decided to put them in her mouth. Startled slightly by the salty taste, she soon adjusted and licked herself clean, rather enjoying it. Deciding there was nothing she could do to clear up the mess on the floor, she turned and left, hoping no one would discover it. At least they wouldn't suspect her!

Uncomfortably, very aware that she could start dripping cum down her legs at any moment, Hermione made her way into the Gryffindor common room. There, she found Harry and Ron inexplicably playing a game of wizard chess. How on earth had he managed to finish class, masturbate, then find Ron for a game of chess? Trying not to dwell too much, she walked over.

"Hey, how was your afternoon?"

"You'd know if you were there. Where were you, anyway?" Ron enquired.

"Library."

"Of course."

"I'm going to go and get changed, I'll be back in a minute." And she headed for the stairs to the girls' dorm.

Quickly dropping her bag on the floor, she removed her robes and began undressing. First untying her tie, unbuttoning and removing her shirt, then sliding her skirt down to the floor. Standing for a moment in only her bra and undies, the considered touching herself to get her own back on Harry. But alas, for the first time in memory she wasn't horny! The spell was working after all. Maybe later. She slid her hands down the side of her hips, and pushed the garments down her legs. Gloopy, viscous cum stuck to her, causing strands to join her to the cotton. Slightly grossed out by the sensation, she hurried up, first dropping them to the floor, then picking them up carefully and placing them in the laundry basket. She wandered into the bathroom, took some tissue and cleaned herself up as best she could. Picking some clean underwear, jeans and a T-shirt, she redressed and headed back downstairs.

"Where's Ron?" She asked, noting the empty chess board and empty chair.

"He won, and went off to watch Fred and George terrify Professor Flitwick with a firework and an enchanted door knocker. Are you going to sit down?"

"Yeah. We need to talk."

"About?" He asked, innocently.

"You know what." She playfully glared at him. "I went back to the library after I... we... you know. And I found something, um... interesting." Her voice shook slightly as she prepared to tell all.

"Go on?"

"Well... it turns out this was never intended to be used on men. And the only way to get rid of it is... to have... sex." She whispered the last part, turning pink and glancing around the almost empty room.

"Oh! Well... Hermione... what do you think?"

"Harry we can't... have sex! We're far too young! We're just going to have to live with this for a while. And try not to do anything while the other person is in a public place - I nearly embarrassed myself in front of Cho and Luna in the library earlier."

"Sorry, you started so I thought...?"

"Ordinarily, yeah. Just not in public."

"What about tonight?"

"What about tonight what?" She eyed him suspiciously.

"What if I wanted to... you know... in bed later."

"That would be fine." She blushed again, getting slightly wet at the thought of her best friend masturbating them both to orgasm, knowing there would be nothing she could do about it.