Title: The Free Use Experience

Summary: In a world where Harry and his twin sister are the Twins-Who-Lived, and their parents survived that Halloween night, there is a sexual social experiment at Hogwarts known as the Free Use Experience. Starting at the age of fourteen, students can willingly volunteer. Willing witches are used sexually, not only in private, but also in public. Harry Potter, a Metamorphmagus, who can change his gender, is forced to volunteer in the Free Use Experience as a girl at least twice a week – including once during the week when he/she must attend classes during the day.

In preparation for the Experience, Harry, his twin sister, Rose, and his girlfriend Hermione have begun a sexual relationship prior to their Fourth Year at Hogwarts.u

Rating: M

Warnings: Free Use, Metamorphmagus/Gender-Bender/Harry, Graphic Sexual Situations Involving Underage Characters, M/F/F Threesomes; Fem-Slash, Sibling Incest, Sex Toys, Orgies; James And Lily Live; Mild to Severe Character Bashing – Ron Weasley, Albus Dumbledore, Severus Snape, others

Ships: Harry/Hermione, Harry/Hermione/OFC (Rose Potter), Harry/Multi, Hermione/Multi, OFC (Rose Potter)/Multi, James/Lily, Sirius/Amelia

Disclaimer: J.K Rowling owns the characters and the world of Harry Potter. I do not. I just like to play in her sandbox. No copyright infringement intended.

Author's Note: Early warning from the very beginning. This story is my most mature and risque story to date. It is not for prudes or readers under the age of 18. This story will probably have some type of sexual situation in many chapters. There will be Sibling Incest (Twincest!), Fem-Slash, and Graphic Sex in many chapters. Read the warnings (tags) and heed them well. If you do not favor (or qualify for) any of this, turn back now.

Even though Harry/Hermione is the main ship in this story, both characters will be involved in sex scenes with multiple characters. It could be argued that Harry, Hermione and his twin sister, Rose Potter, could also be the main relationship (threesome) in this story.

Warnings For This Chapter: Nudity, Sexual Situations Involving Teenagers (Age 14+); Oral Sex; Fem-Slash (Kissing); Incest (Kissing and a non-graphic full-body oil rub)

Chapter 1
Surprises By The Swimming Pool

As the sun shone over Potter Manor in Northampton, England, Harry Potter was wading in the swimming pool behind his large, magnificent home. He grinned when he heard girlish giggling, and turned to find his girlfriend, Hermione Granger, and twin sister, Rose, emerging from the back door of the manor.

Hermione had just arrived earlier that morning, so that she could go with the Potters to the Quidditch World Cup campground the following day. She would be staying with the Potters until it was time to go to Hogwarts. It was not the first time that summer that Hermione had stayed at Potter Manor. She had also stayed for the weekend during the first week of July, and the weekend of Harry and Rose's fourteenth birthday at the end of July.

Harry's mouth watered as he watched the girls remove their t-shirts and jean shorts, revealing their bikinis underneath. He then frowned when he saw them sit down on neighboring chaise lounge chairs near the pool.

"You don't want to swim with me?" he asked them.

"Hold your hippogriffs, brother," Rose said, taking a bottle of suntan lotion from the pocket of her shorts. "We need to put on some suntan lotion."

"Did you forget we're allowed to use magic whilst at home?" Harry asked. "There's way too much magic -"

"- for the Trace to go off," Rose finished, "I know that. I even suggested using sunscreen charms to Hermione. But she thought you might like the alternative."

"Alternative?" Harry asked, looking at Hermione.

His girlfriend smiled mischievously. "I thought you'd want to rub some lotion on me."

"Us," Rose said, "On both of us."

Harry grinned and stepped out of the pool. He walked over to the girls, then knelt onto the ground between them and looked at each of them in turn.

"Who goes first?" Harry asked.

"Hermione," Rose said, "It was her suggestion."

As Harry grabbed the bottle of suntan lotion, Hermione reached behind her back and unclasped her bikini top. Harry felt his penis twitch into life in his swim trunks, as Hermione took off her bikini top, revealing her size 'b' breasts. Harry was no stranger to seeing his girlfriend's breasts.

Harry and Hermione had been dating ever since their first Hogsmeade trip on Halloween weekend of the previous year. For the first two months or so of their relationship, their intimacy was only kissing, snogging, and light groping through their clothes. On Christmas of that year, one of Hermione's gifts to Harry was letting him see her breasts and play with them. In turn, she also gave him a hand-job to completion. This level of intimacy continued until summer holidays. Then during the first weekend of July when Hermione was staying at Potter Manor for the first time that summer, she surprised him by giving him a blow-job.

On Harry's fourteenth birthday, he received an even bigger surprise. Hermione had asked him to make love to her, but that was not her most surprising request. Throughout the month of July, Hermione and Rose had apparently been hatching a plan for Harry for his and Rose's fourteenth birthday. On their birthday, they revealed their plan. Rose wanted Harry to shag her, and Hermione was apparently quite alright with it, as long as she was his first. They even wanted to participate in a threesome with each other and Harry.

"We all know what is going to happen starting this year at Hogwarts, Harry," Rose said, "As the Heiress of House Potter, I am expected to join in the Free Use Experience. I already know there will be several boys who will want to shag me. I want my first to be with someone I truly love."

The Free Use Experience was a sexual social experiment that had been going on since Harry and Rose's own parents were in Hogwarts. Witches – those of whom were willing to participate – would submit themselves to various wizards – most of whom were their age – for sexual experiences, in order to prepare themselves for a husband in the future, which would ensure breeding and extension of Houses, bloodlines and wizarding society in general. No volunteers were exclusive to anyone, not even those whom had boyfriends, like Hermione. All witches were required to take Contraceptive Draughts once a month.

So Harry and Rose celebrated the evening of their fourteenth birthday in a threesome with Hermione, in which Harry shagged both girls twice. Harry and Rose's parents were completely supportive of it, and neither were too surprised that Harry and Rose had sex together. Their birthday had been their only sexual experience so far, neither wanting to continue without Hermione being there.

Hermione took off her panties, revealing her fully nude form. Harry's mouth watered as he looked at the brown patch of fuzz leading to the curve between her legs.

"You want the lotion everywhere?" Harry asked.

"Everywhere," Hermione said, "I don't want any tan-lines."

Harry grinned. Hermione laid down on her stomach and relaxed against the lounge chair. She gave a sharp gasp when Harry squirted a bit of the cool lotion on the small of her back. She then began humming as Harry started rubbing lotion into her skin. Harry took care to rub the lotion everywhere, including her butt, which he focused on much longer than the rest of her body. When Harry was finished with her back, butt and legs, she turned over. Hermione squeaked lightly when Harry squirted a bit of the lotion on one of her breasts.

"Prat," she said, "You did that on purpose, didn't – hmm..."

Her words her cut off by a moan when Harry began massaging her breast, rubbing the lotion into it.

"I wouldn't want you to be in pain from sunburns," Harry said, as he continued, "It would ruin my plans."

"Oh, you have plans, do you?" Hermione asked, grinning.

"Mmhmm," Harry said, "I plan on worshiping you as much as I can during the remainder of the summer."

"Harry," Hermione said, sighing, "I know why you want to do that. I don't have to volunteer for the Free Use Experience if you don't want me to. I know, I've already given consent, but I can still rescind it."

"If you don't volunteer, you won't be considered for Prefect or Head Girl, Hermione," Harry said, "I'm not taking that opportunity from you."

"Alright," Hermione said, "Even though I won't be able to be exclusively yours, I'm still your girlfriend. I promise that I'll always come back to you."

"I have no doubts about that," Harry said, as he moved to her other breast and began rubbing lotion into the skin around it.

"Where do I fit in into this worshiping?" Rose asked.

"You're welcome to join us whenever you want," Hermione said, "Right, Harry?"

"Whenever you want," Harry agreed with his girlfriend.

Rose grinned. Over the next couple of minutes, Harry continued rubbing lotion into Hermione's skin across her body. When he reached to her most private area, he was careful so that it wouldn't get inside her. However, he also rubbed around the skin there, knowing exactly what he was doing to her. He was quite pleased to hear her moan softly to his touch. She pouted when he moved to her legs to continue rubbing the lotion.

"Tease," she muttered.

"You know it," Harry said, grinning.

When he finished with his duties, he leaned toward her and kissed her passionately. She grinned against his lips and returned the kiss. Rose cleared her throat before the kiss could lengthen, and Harry backed away from Hermione's lips. When he turned to his sister, he grinned when he found that she was already naked. Her breasts were slightly smaller than Hermione's, and the area above her pussy completely bare of pubic hair.

Rose proceeded to lay on her stomach, and Harry began his work. Over the next several minutes, Harry took care to rub lotion across Rose's body, focusing on her butt, breasts and crotch as much as he had with Hermione. When he finished, Rose gave him a passionate kiss.

When Harry stood up, Hermione giggled, and he looked at her.

"Did you get excited rubbing lotion on us?" Hermione asked, as her eyes sank toward his crotch.

Harry blushed; rubbing lotion on the girls had given him an erection. He was rather hoping he could hide it until he got back into the pool.

"Are you surprised, Hermione?" Rose asked, "He is a boy who has just had his hands all over us. Frankly, I'd be offended if he hadn't had this reaction."

"I'm not surprised at all," Hermione said. "Something needs to be done about this. Swimming like that would probably be very uncomfortable."

She tugged on his trunks, and brought him back over to her. She then untied his trunks, and pulled them down, revealing his erect six-inch penis.

"Lay down on the chair, love," Hermione said, as she slid down the chair.

Harry stepped out of his trunks, and sat down on the chair, then relaxed. Hermione situated herself between his legs, and leaned her head toward his penis. She brushed her tongue across the underbelly, and repeated this motion five more times, before rubbing it around the sensitive tip, making Harry moan softly. She then wrapped her mouth around the tip, and proceeded to swallow him. Harry was quite surprised to see her take his entire penis inside her mouth and halfway down her throat. The last time she had done this, she could only take half of him inside her mouth.

"Wow," Harry said.

Rose giggled. "She's been practicing. Hermione and I have been keeping something from you Harry. She said she wasn't happy with her performance giving you oral on our birthday, and she wanted to get better. So I convinced Mum to let me copy my dildo she had given me, so Hermione could have one. It looks almost exactly like – well, like you! She said she had been using it, practicing giving oral all month. "

"Practice makes perfect," Harry said, grinning.

He was shocked though. He had no idea that his sister had a dildo. Though it did explain the moans he heard coming from her room sometimes when he passed by her door. He originally thought she was simply just masturbating, but using a dildo was probably even better than simple masturbation with her hands.

Hermione grinned at his comment, around his cock as she looked at him, then continued bobbing her mouth up and down on his penis. Harry brushed his hands through her hair, but was careful not to force her to do anything, letting her do all the work.

Thirty seconds later, he heard Rose humming, and he looked over at her. She had one hand between her legs, as she masturbated herself, and her other hand was rubbing one of her breasts. She winked when she noticed him looking. Then she closed her eyes, laid back against the chair and continued pleasuring herself. Harry relaxed back on his own chair and watched Hermione pleasuring him. Hermione moved a hand between her legs, and started masturbating herself as well.

Seven minutes later, Rose emitted a loud gasp as an orgasm coursed through her body. Hermione's orgasm came moments later, causing her mouth to vibrate around Harry's penis. It was all he could take. He, too, had an orgasm, his seed erupting like magma between Hermione's lips. Hermione raised her mouth to the tip of his penis and milked him, swallowing every bit. The first time she had given him a blow-job and had swallowed his seed, he had been quite shocked. He didn't think she'd be the type of girl to do that, but she said she loved it, and loved the taste of his seed.

When Harry's orgasm subsided, Hermione backed away and stood up. He pouted when both Hermione and Rose walked over to the pool and jumped in. Apparently neither wanted actual sex just yet. However, he was quite happy that they decided to swim nude.

Deciding he, too, would swim nude, Harry stood from the chair proceeded to jump back into the pool. Over the next couple of hours, the trio swam, played, splashed each other, and just generally had innocent fun in the pool. The only intimate things they did was share kisses. Harry was no stranger to seeing his girlfriend and sister kissing; they had kissed during their threesome on his and Rose's birthday.
Roughly two hours after they had started swimming, Harry and Rose's mother, Lily, emerged in the back yard. She did not look at all surprised, or embarrassed to find them swimming in the nude, and only Harry felt a slight bit of embarrassment at his mother seeing him; even though he knew she couldn't see much of him due to the water.

"Harry," Lily said, then waved a scroll of parchment in her hand, "You received post from Professor Dumbledore. I don't know what it is about, but it must be important."

"Thanks, Mum," Harry said.

"Dinner will be ready in two hours," Lily said, "Your father should be home by then. You can swim for another hour or so, but give yourselves plenty of time to get ready for dinner."

Harry, Rose and Hermione promised they would. Lily set the scroll on the table near the lounge chairs, and returned inside the Manor. Harry stepped out of the pool, and walked over to the table, picked up the scroll and sat down on one of the chairs. He unrolled the scroll and began to read it.

Mr. Harry Potter,

Greetings. I hope you've had a wonderful summer. Your father mentioned in passing earlier this summer that you and your family are going to the Quidditch World Cup. I hope you have a joyous experience. I wish I could attend the event, but I am afraid I'm a very busy man here at Hogwarts.

I'm afraid my reason for writing this letter isn't exactly a pleasant one. As you are probably aware, there is a special committee in the Ministry of Magic that focuses on the laws and regulations surrounding the Free Use Experience. The Head of the committee met with me yesterday with some unfortunate news. You see, the committee is well aware that you are a Metamorphmagus, capable of cross-gender transformations.

As you know, earlier this summer, you gave your consent – with your parents' permission – to participate in the Free Use Experience. It wasn't until yesterday, that I was informed of a stipulation concerning Metamorphmagi. I truly wish I could have had this information earlier and I expressed this to the committee. However, they were resolute with their decision.

Because you gave your consent to participate in the Free Use Experience, I have no choice but to inform you of this stipulation. For two days a week (at least – and one of the days must be during the week), you will be required to be in your female form and join the fairer sex in their half of the Free Use Experience, following the guidelines that the volunteer witches will be required to do. As you are capable of becoming pregnant, you will be required to take Contraceptive Draught each month.

Please know, Mr. Potter, that I'm not entirely pleased with this situation, but rules must be followed. You are, of course, welcomed to back out of your decision before the first of September. However, I'm sure you know the repercussions of not participating in the Experience.

If you have any questions which you don't wish to talk to your friends or family about, please know I will always be happy to help. Or you can speak to Madam Pomfrey or any member of the staff, and I'm sure they will be just as willing to help.

Wishing you a pleasant remainder of your summer,

Albus Percival Wulfric Brian Dumbledore
Headmaster, Hogwarts School of Witchcraft and Wizardry

Harry couldn't believe what he had read, so he read it over once again to make sure he had not misread anything. However, it was the same as he had read the first time.

"Harry?" Hermione asked, "What's wrong? You look peaky."

Harry set the scroll back on the table. He didn't say anything until he stepped back into the pool.

"You've heard of the committee that deals with the Free Use Experience?" Harry asked. "Right?"

"Of course," Hermione said, "They deal with the laws and guidelines of it all."

"Apparently there is a stipulation when it comes to Metamorphmagi like me," Harry said. "If I want to volunteer to be a part of the Experience, I will also be required to – er – be a female for two days a week. At least."

Hermione and Rose both gasped.

"You mean," Rose said, "You'll have to... follow the same guidelines we witches have to follow?"

Harry nodded. "That's what Dumbledore says anyway. Apparently he met with the Head of the Committee, who told him of this stipulation."

"But I – I've read the rulebook on the Experience!" Hermione said, "I didn't see that stipulation!"

"How many male-oriented Metamorphs do you know, Hermione?" Rose asked, "As far as I know, Harry's the only one. Like Tonks, most Metamorphs are female-oriented."

"So you're saying," Hermione said, "Harry might be the first male-oriented Metamorph to volunteer in the Experience."

"I'm quite sure the law was written after Harry gave his consent earlier this month," Rose said. "Obviously they have a list of all consenting students. When they realized you consented, Harry, and realized what you are, they discussed this."

"You can still back out, right, Harry?" Hermione asked, "Maybe -"

"No," Harry said, "It's like I told you earlier. I don't want you to back out, because the repercussions are too much to handle. Not only will you not qualify for the Prefect and Head Girl titles, but it might ruin any chances of a normal life in wizarding society."

"Participation usually leads to getting considered for jobs," Hermione said.

"And since you're a Muggleborn, you'll need that leg up," Rose said, "Especially since it tells people that you're willing to participate in the betterment of wizarding society. And if you marry Harry -"

Both Harry and Hermione blushed at that thought, but they smiled too.

"It could ruin the status of the House of Potter," Hermione spoke up, "to be associated with someone who didn't choose to volunteer."

"Plus you could basically count your relationship as boyfriend and girlfriend over," Rose said, "Your relationship will be welcomed, as long as you're willing to not be exclusive to each other."

"I'm not backing out of this," Harry said, "This is just an unexpected hurdle."

"But, Harry," Hermione said, "For two days a week, you'll have to – to –"

"- to let other boys use you," Rose finished, since Hermione didn't seem to want to complete her thought. "Whenever – and nearly wherever – they want. I've even heard that the Professors welcome it in their classrooms, as long as your classwork is done, and grades are above a passing level."

"As much as I hope that isn't true," Hermione said, "I wouldn't be surprised if it is. Harry..."

"I'm going to do it," Harry said. "If only because both of you have volunteered."

Hermione smiled, and swam over to him. She grasped his hands in hers and looked at him.

"You're too good, Harry," Hermione said, "That's why I love you."

"I love you too, Hermione," Harry said.

Hermione smiled then leaned toward him and kissed him softly. Harry returned the kiss. They parted half-a-minute later. Rose, meanwhile, was looking rather thoughtful as she gazed at them.

"What's up, sis?" Harry asked.

"I'm thinking," Rose said.

"About what?" Hermione asked.

"The reason you and I decided to shag Harry," Rose said, "was so that we could enjoy our first time with someone we loved. I think we should return the favor."

"Ooh," Hermione said, grinning, as she looked from Rose to Harry, "I like that idea."

"You're his girlfriend," Rose said, "It should be you."

"What?" Harry asked, confused.

"It will be Hermione's job to pop your cherry, Harry," Rose said. "I'm sure we can fashion a strap-on from our dildos."

Harry's eyes widened as he realized what she was saying. "So – er – you mean -"

"Between tonight and the night before we return to Hogwarts," Rose said, "You're going to be on the receiving end of a shag... more than one if I have anything to say about it. Which I do. We have to prepare you for the real thing. Don't worry, Harry. We'll be gentle. Right, Hermione?"

"Of course," Hermione said, grinning.

"But you know what else this means?" Rose asked, "We need to take you shopping, Harry. Hopefully the World Cup doesn't last too long. We need to go to Diagon Alley, and get you fitted into female outfits, including school outfits... skirts, and all that."

Hermione grinned. "I've been looking for an excuse to go shopping for girls' clothing with you, Harry. This will be fun."

Harry rolled his eyes. He wasn't exactly a stranger to shopping for girls' clothing. His mother had made it a tradition to go shopping every summer for girls' outfits for Harry, just in case the urge to turn into his female form popped up.

"We'll have to talk to Mum and Daddy about this, you know," Rose said.

"Mum and Dad?" Harry asked.

"Of course," Rose said, "You can't keep this news from them."

Harry groaned. "Right. I'm sure they'll take that well. I've never had to be a girl for any period of time at Hogwarts."

"Don't look so disappointed," Rose said, "This could be fun."

"Fun?" Harry echoed, "Maybe for you. I never thought I'd have to do the Free Use Experience with blokes. I don't even know where to begin."

"We'll help you," Hermione said.

"Definitely!" Rose said, then grinned, "Hey! I'll have to talk to Mum about getting you a dildo to practice on too. We could copy mine, like I did for Hermione."

Harry groaned, and Rose and Hermione chuckled at his reaction.

The trio swam for another hour before they decided it was time to go inside. They dried off, put their swimwear back on and headed back into the Manor toward their bedrooms. Hermione had her own guest room while staying at the Manor, though she hadn't used it for sleeping since before Harry and Rose's birthday, when she had slept in Harry's bed.

Harry was the first to return downstairs after getting dressed back into his normal clothing. His father, James, had arrived home from work, and was in the kitchen with Lily.

"Dinner will be ready shortly," Lily said.

"Okay," Harry said, "Um, I need to show the two of you what Professor Dumbledore wrote me. It's – er – not exactly a good thing."

He passed Dumbledore's letter to James, who began to read it. He looked quite shocked, but also rather amused, by the time he finished it. He handed the letter to Lily, but said nothing yet. Harry watched his mother read the letter. She, too, had the same look of shock on her face, though she wasn't as amused as her husband.

"Why didn't we know about this until just now?" Lily asked, "I've never heard of this – this stipulation."

"Rose thinks it was a recently made law, done after I gave my consent," Harry said, "She and Hermione think I am the first male-oriented Metamorph to deal with the Free Use Experience. So when they heard I gave my consent, and realized what I am -"

"They created a law that requires you to be a female for two days a week," James said, "And follow the guidelines witches have to follow if they volunteer."

"This is outrageous," Lily said, "I am going to write to the committee about this – hell, I'll send 'em a howler! - and demand they change it. I can count on both of my hands how many times Harry's changed into a girl ever since he completed his Metamorph training. There's no reason you should have to do this. You should take back your consent, Harry. Tell him, James -"

"No," Harry said, resolutely, "I'm going through with it. I gave my consent, and so did Hermione and Rose. We all know the repercussions of not volunteering, and I am not going to put the girls, nor our House through that."

"Good man, Harry," James said, proudly. "I'm sorry you have to – ahem – deal with this, of course. But I know you'll face it like a Potter should. Head on, and a brave face."

"Are you sure, Harry?" Lily asked.

"Yes," Harry said, "Er – Hermione, she – she said she'd help me prepare for it."

James snorted lightly, then exclaimed when Lily hit him on the back of his head.

"Rose and Hermione also think," Harry said, "that I need to go shopping for girl's clothing."

"Well, I suppose you'll need a couple feminine school outfits," Lily agreed with a sigh, "You can't go around dressed in your male outfits when you're required to be a girl twice a week... and one of those days during the week for classes."

"I'm sure we'll have time to go to Diagon Alley after the World Cup," James said. "Definitely won't have time before then. We have to meet the Portkey at seven-fifteen tomorrow morning. Luckily, we won't have to walk too far from here. Just through the forest behind the Manor and into the field on the other side. We'll leave at a quarter-past-six."

"Early bedtimes tonight then," Lily said.

Harry's Metamorph abilities were the only reason he hid his blush. If the girls' behavior was anything to go by, they definitely would not be going to sleep too early that night. Perhaps he could compromise with them, however.

Definition of Free Use as seen in this story: Sexual Situations with anyone (as long as they are willing, and consenting age, in this case 14 and above), anywhere (with some limitations), at anytime with little risk of anyone caring enough to actually interrupt or stop the situation. Only a few specific rules apply and must be followed.

This story is also featured on Archive Of Our Own (Ao3) under my penname FurySerenity. On that website, the story already has several chapters. I will one-to-two chapters a day here on FFN until I catch up with the story on Ao3. Feel free to read it there if you want to read ahead.