Futanari - Little sister

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Scientist confronts his feelings... as well as magic.
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MrIllusion
MrIllusion
4,825 Followers

Very important note: this is a very crazy story! It is not for everyone. In it, you'll find something akin to transsexual transformation, incest, deepthroating, anal and magic. For those of you who already know what futanari means, know that I've done my own version of it, mixing the classic futanari concept with other magical stuff.

Edited by: Pope1944. Thanks!

*****

Ben was looking forward to the week-end with his family as he turned the last corner before arriving. As a third year medical school student, the 24 year old missed his parents and little sister. He wouldn't admit it to her, but he did miss Lily quite a lot even though she could, sometimes, be a pain. She would probably leave home for college next year, at nineteen, and sometimes he wondered if it would be a good idea to ask her to come live with him.

He shook his head and forgot about that as he knocked and opened the door. He was warmly greeted by his parents. Lily wasn't there, but he knew she'd arrive later. Ben spent a few hours with them until the moment, around five, Lily arrived. Ben's heart skipped a beat when he saw his sister bouncing up the stairs. Ever since she had bloomed through her teenage years, Ben had been secretly attracted to his sister. For a while that attraction had been so powerful that he had remained single for a year and a half!

Lily seemed as lively as ever as he watched her through the large window, her two braids bouncing behind her as she ran to the door. She exploded into the house, there was no better word for it, and threw herself into his arms. Lily had always been full of life and energy. As he squeezed her hard, eyes closed with a grin on his face, Ben took a deep breath and took in her unique scent. She kissed him on the cheeks before sitting in front of him at the table to catch up on news.

As they talked Ben had to work to focus on what she was saying. He was spellbound by her long dark red hair, her faint freckles, he small nose and generous lips who were, as ever when she was around him, constantly smiling. But most of all, Ben had to confess as he stared at her, he was captivated by her bright blue-green eyes. She had incredible eyes that seem to sparkle under the merest light, and when she was in sunlight they were positively phenomenal. Lily sometimes said that she wished she had ordinary eyes as she was tired of the attention, tired of the fact that people bothered her continuously with compliments. But Ben knew she was lying: Lily loved her eyes.

A while later, as she got up and moved around in the kitchen, Ben's eyes stole a few glances at the rest of her. Lily was on the short side of the average and was pretty slim all around: small sexy breasts, a tiny waist that made her lean hips seem bigger and long legs that were stronger than their slim shape would lead one to believe.

Her short skirt, white knee high socks and tight tank top highlighted her slender shape. Overall, she looked like a human female version of a cat. In the manga and anime world he really liked, he often saw girls cosplaying as cats. While he liked big breasts as much as the next guy, Ben thought that human versions of cat should look exactly like his sister: lean, thin and agile.

Their evening together as a family, the first in a long while, was very pleasant. Yet as they talked Ben slowly observed that whenever his sister wasn't talking and thought nobody was looking at her, her smile faded. He had no idea why. Maybe she had recently broken up with a boyfriend? He didn't feel like asking her what was wrong right now, not in front of their parents in any case.

Later that night, as he was lying on the uncomfortable sofa bed, he thought about Lily again, trying to figure out what could be wrong with her. Given that they didn't see each other often he sighed, knowing he couldn't divine it out of thin air. He resolved to find the time to ask her about it tomorrow.

As luck would have it, he found himself alone with Lily for breakfast. When she walked in the kitchen wearing a tank top, and probably only that, Ben almost choked on his toast. She wasn't wearing any bra, that much was obvious, and he couldn't detect any panties under the tight fabric. The tank top covered, at most, a third of her thighs and the effect was remarkable. Lily had wrapped her hair in a high bun above her hair and he stared at her, his breath taken. He felt a surge of pleasure in his heart and an equally intense sure of blood between his legs.

Ben bit his lower lip, closed his eyes and tried to focus his sharp mind on the fact that she was the last person he should have these kinds of feelings for. A deep breath later, he wished her good morning. Lily startled when she heard him: she hadn't seen him yet and had probably thought that she had been alone. But Ben felt both apprehensive and glad when Lily walked to the table and sat down wearing nothing but her tank top. He would have been relieved but disappointed if she had gone and changed, but now... now he had to deal with his inappropriate feelings.

Instead of doing small talk, Lily surprised him with a question "I have a strange question for you, brother." She smiled, but without further preamble, asked "I know you like anime and manga, but do you like futanari?"

Ben's eyes opened wide when he heard her question, and he managed not to spit his cereals all over the table. "What?" he asked after swallowing. "Are you serious?"

"Yes. What, we're both adults?"

"Yes, but..."

Futanari was a genre of hentai where females had huge cocks and, sometimes, males had breasts. It wasn't, at all, a subject Ben had ever thought he'd discuss with his sister. Especially not while she was practically naked in front of him! "Look, Lily... I do like it. But..." he paused, then added "why don't you tell my why you're asking me that? What prompted the question?"

He was surprised by her reaction. Very briefly, he saw her expression change and she seemed afraid for a second or so. "No reason, just curious... I like it too." She said quickly. But very soon she changed the subject and stood up to go back to her room. Ben was so surprised that he didn't even think to look at her lovely ass as she walked away. Why had she asked about that?

Ben actually loved futanari hentai, either in manga or anime form. But damn! Talking about that over breakfast? What had gotten into her? Then he realized that their parents would be back soon and that she'd had no other option to talk to him alone. After he finished his breakfast Ben stood and was headed for her room when he saw their dad's car stopping in the driveway. Shit. No time.

The rest of the day offered no other opportunity, but seeing that Lily was obviously feeling bad, he managed to find a minute to tell her that he was sorry for reacting strongly at breakfast. She brushed it off saying that it wasn't important, but Ben knew that it was. He was hoping that we would find ourselves alone later that night, but she decided to turn in early.

So once again he found himself alone in the damned sofa bed, thinking about Lily. About half an hour later, he suddenly heard the door opening in silence. "Ben? Are you awake?" asked Lily in a very low whisper.

"No, I'm not." he said sarcastically. "What's up?" he asked.

In the pitch darkness she came and sat on the edge of the bed. "I have a question I need to ask you. A question to you as a med student." she whispered. "Two weeks ago I went to a party. A very peculiar party. Let's say there were strange people there, with strange, er... strange pills."

"Oh. I see." She was curious about drugs. Even though Ben couldn't see her, he could sense that she was very nervous. "Go on."

"Well, I took a few and had the most epic trip imaginable. Life changing, in fact."

Ben smiled when he heard that she was smiling herself. She even giggled before continuing. She probably wanted to know what those pills were and if he knew if they were dangerous or not. But he was wrong. "So I probably spent a few hours in that small room, tripping with four or five other people." Then she paused and remained silent for a few minutes.

Given that the silence was becoming awkward, I said "Go on Lily, I won't judge. If you're worried about something, please let me help you."

"Hmmm." she said, but as Ben heard her take a deep breath, he knew that her smile was gone and that she was nervous again. "Mind if we go to my room to talk? I don't feel comfortable here, with our parents on the other side of the wall."

"Sure..." he said.

Ben stood up to follow her and saw that she was still wearing the same tank top as this morning. She probably slept with it every night. "Focus!" he thought. They went downstairs, went to her room and closed her door behind them. When Ben saw Lily jumping in her bed and slipping under the blanket, he frowned. That was another sign that she was nervous. Sitting on the edge of her much more comfortable bed, Ben waited for Lily to talk. She turned her little bedside lamp on, looked at him and said "Listen Ben... It wasn't my first time with psychedelic drugs, but this was weird... Promise you won't judge me?"

"Yes." Ben said.

"I know you must have had some psych classes, and learned that hallucinations reflect the innermost thoughts of the person." she said.

"Yes, sometimes. But other times it's just random images that don't mean anything." Ben replied.

"Ok then." One last deep breath before she said "I hallucinated futanari for hours!"

"Oh!" Ben said, finally getting an explanation! Unexpected, but an explanation nonetheless.

"Shit! It was crazy!" Lily said. "I had seen a couple of anime with futanari stuff, but this was beyond my wildest imagination! At first I was an observer, seeing countless girls with dicks and guys with breasts having sex in endless positions and arrangements of two three, four or more people at the same time! Soon after that, I was pulled in and felt myself having sex with all sorts of hermaphrodites, felt myself penetrated in all of my holes, sometimes all at once..."

When Ben's sister paused, he himself took a deep breath and cursed himself for not thinking of putting his pants on. As Lily talked, his mind filled with images from his favorite futanari hentai and his cock grew and grew. Looking at Lily, Ben saw that her nipples were both sticking clearly through the thin fabric. And she wasn't done. "Eventually, I felt a penis growing from my pussy, as if my clit was transforming into this monster of a cock, growing and growing until it reach ten or twelve inches and even more! I saw myself fucking girls while their cock were slapping against my belly, against my breasts... Shit! When I came, I felt my entire body glowing, felt myself turn into a sexual bomb of raw pleasure! I even had a furry tail!"

Ben, closing his eyes and biting his lower lip again, turned slightly on the bed as Lily talked. His erection was painfully pressed against his boxers, threatening to tear through them! He wasn't anywhere close to being ten inches long, but right now his cock felt like it, trapped as it was in his boxers. He dearly wanted to release the pressure, but couldn't do it now. After a brief pause, Lily said "So, am I crazy, big brother?"

Ben stared at her, looking right into her magical blue-green eyes, Ben calmed himself and said "Of course not little sister. In fact, I think I'd pay a lot to have this kind of trip!"

"Really?" she said, laughing. Ben could feel her nervousness melting away.

"Yes. I do like futanari, even if it's something I never thought I'd talk with you!" he laughed.

And then she shocked him "Are you hard, brother?"

"What? No, no... Must be a trick of the light."

Lily didn't reply, clearly unconvinced. Nevertheless, she seemed much better. Still, with his experience at listening to patients talk about their problem, Ben suddenly had a nagging feeling that Lily had something else to say to him. "Don't worry about it... Just enjoy the memories and make sure not to overdo those pills, OK?" he asked. Lily nodded, and judging by the way she was looking at him, he was now convinced that she wasn't finished. But she nodded again and thanked him.

Ben got up, making sure to hide his erection from his sister and walked back to his room. On his back on the bed, he pushed his boxers down and grabbed his cock. He moaned as soon as he started jacking off, images of futanari filling his mind. But soon he was seeing his sister in his fantasies and he stopped. He had often been tempted to masturbate while thinking about his sister, but he had always stopped himself. "Just too weird"! he had thought.

And now in his mind's eye his sister had a huge cock between her legs and the temptation was even greater than usual. Ben had never felt any sexual attraction to guys, but couldn't deny that his fascination for futanari meant that one day he would have to do some serious soul searching. He wasn't a homophobe, but neither had he ever thought of himself as bi. At all. Yet seeing those anime girls with huge cocks... Shit.

But his sister? Fuck! Ben laughed on the bed, letting his cock rest against his belly for a moment. Would this be the first time he allowed himself to masturbate fantasizing about his sister? Ben was sorely tempted! But before he could make a choice, he heard his door open again. In a flash he pulled his boxers up again and pulled the blankets to his waist. "Ben? I need to tell you something else... Would you mind coming back to my room?"

"Sure, no problem." he said, noticing the tension in her voice. "I'll be there in a sec."

After she left Ben stood up, stretched, took deep breaths and tried to clear his mind. He couldn't walk to his sister's room with an erection in his boxers! But he was so focused on getting his cock down that as soon as he did, he went to join her, forgetting once again to put his pants on. And so as he sat on her bed again, he cursed himself a second time.

"Ben... Shit, this isn't easy. Ben, is it possible that such pills could have physical effects on my body?"

Ben frowned, snapped into focus by her question. He was worried about Lily, because there were, indeed, drugs that could cause physical damages. "Yes, it is." he said calmly. "What are your symptoms..."

"Well, it started the day after the party. I spent the day feeling a buzz in my body."

"A buzz?" Ben asked.

"Yeah. I don't know how else to describe it. A faint buzz in my stomach."

"Hmmm. Ok. What else"?

"Well, I've been feeling a lot hornier ever since that party." she said in a small voice.

"That's understandable, Lily. Intense climaxes like what you describe can have long lasting—"

"A lot hornier Ben. I think about sex all the time." she added.

And suddenly, his sexual mind was fighting to regain control over the medical student in him. "Oh?" he asked, trying to gain time.

"I have to masturbate at least twice every day, and... Oh shit... This isn't easy."

"Just go ahead Lily. Just say it." Ben said.

Lily reached over and closed her lamp. In the darkness, she said "Well, ever since that futanari trip, my body has begun to change."

For a moment, Ben wondered if his sister wasn't going to tell him that she had a cock. But no! That was completely crazy! "What do you mean?" he asked in what he hoped was a professional voice.

"It's hard to describe... At first it was just weird feeling, sensations I'd never had before... Ohh."

When Lily moaned in the darkness, Ben's eyes shot wide opened. Was she masturbating? Impossible! Then he heard the sound of flesh rubbing against a blanket. When she started talking again he could hear her voice quivering. "And then after a while I felt this urge to masturbate. As I played with my clit, it began to swell..." Ben's rational mind tried to save itself one last time by acknowledging that a clitoris could indeed swell with blood when excited. But that help didn't last very long. "Oh fuck..." Lily moaned again, clearly this time. "And now, when I masturbate, my clit transforms into a cock... Shit, a very real cock."

And at the same time, he heard a new sound that he nevertheless was very familiar with: the sound of a guy jerking off under a blanket. But it wasn't a guy lying next to him. Briefly he wondered if Lily could simply be teasing him, but even though that explanation made more sense than Lily growing a cock, the two siblings had never shared anything remotely sexual. This would be completely crazy. Then again...

Suddenly, Lily grabbed his hand, pulled it under her blanket and guided it to her pussy. And her cock. Ben gasped when he felt his fingers closing on a hard cock. On a big hard cock. He pulled his hand away, then closed his eyes, trying to make sense of what was happening. He failed. Groaning and getting up, he paced the room, trying to decide if he wasn't drugged himself. Had someone given him a dose of something? Impossible! But so was this! So was his sister growing a cock! Fuck!

Sitting back down, he looked at his sister. Her eyes were now glowing in the literal sense of the word. He blinked, then looked again. Now her eyes looked normal. Well, blue-green, but normal for her. "What the fuck is going on?" he wondered. "Lily..." he said. "What... How... fuck. This is impossible! Even with genetic modification, it couldn't grow so quickly. And in any case there's nothing, not even cutting edge research that could do this... Shit!" He knew his mind was running around in circle.

Ben reached under the blanket again and touched his sister's cock. It was bigger than before. When she moaned, he was reminded that she wasn't just a curiosity lying on a lab table. It was his sister and she was both nervous and sexually excited right now. Ben closed his eyes for a moment and took a few deep breaths. "Lily. Can you describe the pill and anything you can remember about that party?"

She did. As she talked, he pulled his hand away from her cock, but let it rest on her thigh. As she talked, she kept masturbating herself slowly. She said it was to keep it there. If she stopped it would disappear, be absorbed into her again. This entire situation was completely unreal! Ben realized that it would be unreal even if she didn't have a cock: earlier today he had been uncomfortable about the fact that he was lusting after his sister, and now he was listening to her talking, with a hand on her thigh while she masturbated. Crazy enough even without the unnatural cock!

When she was done, Ben shook his head, having learned nothing that could help him figure this out. He sighed. "And, er, the rest of your, well..."

"My pussy?" she said in a small voice, and Ben felt a spasm of sexual pleasure between his legs.

"Yeah. Is it, normal?"

"Yes. I think so. Can you check?" she asked, still in that small voice.

Shit. Ben shook his head, but pushed his hand up. After having found the cock, Ben moved his hand down and felt his fingertips touching his sister's pussy. No balls at all. Before he could stop himself, he moved lower still and pushed one of his fingers inside her. Lily's pussy was drenched, more than lubricated enough to let his finger go as deep as it would go. Ben shivered with pleasure as he fingered his sister.

Lily moaned when his fingers slipped inside her pussy. Moving his hand back up, Ben lightly closed his fist around the shaft of that impossible cock and kept moving up. Shit! It was big! At least eight inches! As if reading his mind, Lily said "And it can grow much longer than that..."

"How long?" Ben asked, entranced.

"Longest so far was twelve inches."

"But that's insane!" he said.

"I know..." she replied, but she was moaning, enjoying her brother's hand on her cock.

"What happens when you stop masturbating?"

"It disappears completely. And I look like a normal girl." she said.

MrIllusion
MrIllusion
4,825 Followers
12