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Fumina and Kaoruko had been competing for Sekai’s attention for a while, and while Sekai was more devoted to his sister than they expected, Kaoruko kind of had to respect him for that. She looked up to Susumu, her older brother who had taught her everything she knew about Gunpla, and her younger brother Tateo did the same for her. She was close to her brothers, and as the only girl and the middle child, she relied on someone else, and was relied on by another, at the same time.
She was a chubby girl, which meant she was voluptuous in other places. She was changing out of her St. Odessa uniform into her pajamas in the bathroom when Susumu walked in. The little sister who’d admired him so much had developed a plump chest, with inverted nipples that only made her look cuter. She was growing in a fine-looking bush, and her ass was quite round. She was starting to look like a woman. She’d bathed with her brothers so much that she thought nothing of them walking in, but there was something different about this time. She couldn’t help but notice Susumu pitching a tent in his shorts at the sight of her.
“Susumu, I didn’t expect you to get hard from your own sister,” said Kaoruko. “But then, I am the perfect girl for Sekai.”
“You can’t stop calling his name when you’re playing with yourself,” said Susumu. “Are you that desperate for a cock? Because you can use mine if you’re feeling thirsty. You’ve filled out really nicely.”
“My beloved Susumu, letting me use his dick? You must be joking,” said Kaoruko.
“I’m not joking,” said Susumu, removing his towel to reveal his hard, throbbing cock. “I’ve got a hard-on right now. You know what to do, get started.”
Just before Kaoruko started attending St. Odessa, she had lost her virginity. To her older brother. While Susumu wasn’t quite the top-tier Gunpla player that Sei and Reiji were, he was still well known. He had become a handsome, if somewhat plain looking, young man in the intervening years, and he noticed his sister was filling out as well. She admired him so much that when she asked him to take her virginity, he didn’t refuse.
They had kept it a secret from their parents, but two years ago in the middle of the night, Kaoruko had sneaked into her brother’s room. She sucked his cock and let him pound her pussy until the two of them were exhausted. Afterwards, they took a bath and had sex again. Since then, the two of them had been having sex with each other at least once a month when they could find the time. It looked to be continuing this way forever, until Kaoruko met Sekai.
Kaoruko bent down, and licked the underside of her brother’s dick. Her tongue traveled up the length, leaving a trail of saliva behind. Now glistening with her drool, she rubbed her tongue against the underside of his glans, watching it twitch and start to drip with precum. Here she was, playing with her brother’s dick in her underwear. The idea of it was making her so wet that a stain was starting to appear on her panties, drawing attention to her hard clit.
She sucked his dick, moving her head up and down his shaft. It was covered in her saliva, shining and slippery. The more she slurped at his cock, the more she felt it throb inside her mouth. She moved her fingers towards his balls, massaging them to get his sperm swimming. She wanted them to be active when they went into her stomach and her pussy. Susumu’s cockhead dripped with precum, about to explode inside his sister’s mouth.
“Kaoruko... you’re too good...” said Susumu.
“Of course, dear brother,” said Kaoruko. “I’ve been sucking your cock for a long time. I know all of your weak points.”
Susumu reached behind his sister’s back, unhooking her bra and letting it fall to the floor. He caught a glimpse of Kaoruko’s heavy breasts, her inverted nipples twitching in excitement. He reached his hands down, groping her chest, fondling it between his fingers. His digits sunk into her breast flesh, kneading it and making them jiggle. Kaoruko’s sucking became stronger as Susumu’s fingers neared her nipples.
His fingertips dug into her nipples, rubbing against them. Kaoruko moaned. Her nipples were sensitive, and they were twice as sensitive when they were hard. Her brother pulled them out from their pink hiding place, making them stand erect and throbbing. They were nicely shaped and nicely colored, standing atop her breasts like cherries on the world’s wobbliest pudding. With the tips in his grasp, Susumu began shaking his sister’s breasts about, watching them jiggle and wobble. The vibrations spread all the way down to her belly fat, making even her navel shake.
“You’ve gotten so much better at this, Kaoruko,” said Susumu. “You’re not letting your teeth touch it, and you know all my sensitive parts. Make sure you swallow my cum. We don’t want to dirty the bathroom.”
Kaoruko nodded in approval. She rolled her brother’s cock around with her tongue, pushing it to the side of her cheeks. Trapped in her warm and sticky mouth, she massaged the shaft, getting so close she could feel his hairy balls slapping against her chin. Those balls full of thick, rich semen that filled her throat and pussy. She loved it so much, she craved for it. Until she had met Sekai, she thought her brother had the best cum in the world. Even now, she still loved it.
“Kaoruko, before I cum,” said Susumu. “Use those tits that you’re so proud of. Shield my cock in your big, fat breasts.”
Kaoruko released her brother’s dick from her mouth, a trail of saliva rolling down from her lips. “Right away, dear brother.” She picked up the underside of her heavy breasts, squishing them against Susumu’s cock. Her breast pressure was intense, the fat in her tits holding her brother’s cock tight. With his glans poking through the valley of her cleavage, she reached in and got back to sucking. The slurping noises could be heard from outside.
As Kaoruko worked her brother’s shaft, Tateo, who had to use the bathroom, saw them going at it. He was still young, but he adored his older siblings, and wanted to learn how to play Gunpla from them. He knew that Susumu and Kaoruko were close, but seeing his older brother, cock out and his older sister slurping down his freshly splattered cum from the inside of her mouth made him feel something that he wasn’t sure about. In his shorts, he felt blood rush to his dick, the sign of a growing erection about to burst forth.
“Susu? Kaoru? What are you doing?” he asked.
“Tateo, we’re just having a private talk,” said Kaoruko. “One where I needed to be on my knees.”
As Tateo ran out of the bathroom, Kaoruko caught a glimpse of his hard cock underneath the towel. He was just starting to hit puberty, but that was a Sazaki cock for sure. Kaoruko was certain that in a few years, Tateo’s dick would be as thick and rugged as Susumu’s. She wanted to show him how to use it properly, and thought it was her duty as his sister to make sure that his first time was done properly, in the Sazaki way.
She found Tateo sitting in the middle of the living room, looking at a Hyper Gyanko Gunpla that he had built. Kaoruko couldn’t believe she had lent her likeness to this thing, but she was mostly doing it to one-up the popular Super Fumina. She wasn’t going to let him take Sekai’s attention with her form-hugging athletic wear. She wasn’t quite as slender as Fumina, but that was her charm. She had something that Sekai - or her brother - could grab onto, and she was proud of that.
Still sticky from the bathroom, the only thing she had donned was a pair of panties. Her voluptuous bosom, nipples no longer inverted, was bouncing freely as she took a seat beside him, her breasts bared.
“Tateo, were you going to tribute a Gunpla of your older sister? You naughty, naughty boy. The Plavsky particles wouldn’t be able to properly disperse if you did that,” said Kaoruko.
“But I can’t...” said Tateo.
“What part of me do you like the best?” asked Kaoruko. “I know we haven’t bathed together in a while, but while I haven’t grown that much, you certainly have.”
“I like your big butt,” said Tateo.
“Susumu was always more focused on my tits,” thought Kaoruko. “He kept rubbing me until I needed a bra. Then he started sucking and... wow, I thought these two would be rather similar. What do you think of your sister’s pudgy belly?”
“I like that too, but I like your butt more,” said Tateo.
Kaoruko sat beside her brother on the couch. She got on all fours on top of the cushions. She dropped her panties slowly, exposing her soft, round butt cheeks to her brother. He was getting a full look at her asshole and her pussy, both covered with strands of brown hair. Though Kaoruko had showered, thinking of her brother had gotten her all worked up, and she was smelling of sweat and pheromones back there.
“You can do whatever you want with me down there,” said Kaoruko. “Smell it, lick it, touch it. My asshole’s clean. Perfect for my favorite little brother to play with.”
Tateo placed his hands on Kaoruko’s fat ass. He felt his little fingers sinking into her ass flesh, squeezing down on her butt. It was warm and pillowy, a splendid ass that smelled erotic, covered in sweat and the pheromones coming from her pussy and anus. As his fingers left their mark on her cheeks, he bent in closer and took a deep whiff of her butt’s smell. His cock stood on end, throbbing hard in excitement.
He planted his lips on Kaoruko’s asshole, tasting her faintly bitter ass for himself. His warm, wet tongue sliding around her hole made Kaoruko moan. She had always enjoyed playing with her ass on her own, but Susumu had never given it any attention, as much as he loved her breasts and her pussy. His licks were small and awkward, but warm. As his tongue dug deep into the wrinkles of her anus, Kaoruko started to moan.
Tateo’s tongue slipped inside her asshole, rolling around the inside. It was even hotter and spicier inside her ass. As her asshole was coated in saliva, Kaoruko moaned so loudly that she hoped nobody would come in. Her asshole was throbbing, the gyrations of Tateo’s tongue traveling all the way down to her hard clit. Her libido had been left unsatisfied when her blowjob with her brother was interrupted. She had to get it out.
“Tateo, your sister’s going to squirt!” said Kaoruko.
“What’s that?” asked Tateo.
Gyanko pulled her ass forward, removing Tateo’s tongue. She jumped backwards, planting Tateo’s face onto the couch cushion and burying his nose deep in her cleavage, while his mouth was under her hairy pussy. She rubbed her outer lips a slight bit, and unleashed a torrent of hot, bubbly squirt all over her younger brother’s face. She was flushed bright red and sweaty, her body finally having come. She got off Tateo, looking at his face covered in her love juices.
“Tateo, I didn’t think it’d be so much,” said Kaoruko. “I’ll clean it off.”
“It smells really nice. It’s making my weiner feel all weird,” said Tateo. “How do I get this feeling to go down?”
Kaoruko grabbed onto her cheeks, spreading them apart to show her brother her butthole, lined with fine brown anal hair. “Tateo, you’re going to be the first boy to take my anal virginity,” she said. “Put your weiner in my asshole, and we’ll both feel really good. It’s even better than licking it.”
“You’ll let me do that?” asked Tateo.
“Just like me and Susumu were doing,” said Kaoruko. “It’s a family tradition.”
Tateo grabbed ahold of Kaoruko’s butt, guiding his hard dick and balls that had just started to drop towards his sister’s asshole. The head pushed into her tight butt, with her greedy hole swallowing the rest of it in a single stroke. He was now inside her, and the tightness of her ass was beyond what he had ever imagined. He looked down and saw that it was the truth. He really was balls-deep inside Gyanko’s ass, and she was coyly looking back at him, waiting for him to move.
“Fuck me, Tateo,” Kaoruko said.
Tateo’s dick wasn’t very large, but it was rock-hard. What it lacked in length and girth, Tateo substituted with passionate humping, going at his sister’s ass like a dog in heat. His dick fit comfortably inside her bottom, not stretching or hurting her asshole at all. Gyanko raised her ass into the air, squishing her breasts into the couch as she got into the comfortable rhythm of her brother fucking her in the ass.
Every few thrusts, she would squeeze and clench her asshole around his dick, loosening it to tease him. She wanted his first time to last as long as possible, even if his stamina wasn’t much, given his age. She moaned happily, glad to finally have her last virginity taken. She would be so experienced that no matter how Sekai wanted to fuck her, she would blow his mind with her sex techniques. Every slap of her brother’s dropping balls against her pussy made her squirm with delight.
“Kaoru, my dick’s feeling weird!” said Tateo.
“It means you’re about to cum,” said Kaoruko. “Let out all your hot, white spunk in my ass. Cum in my butt!”
Tateo’s first orgasm was inside Gyanko’s ass. Wads of gooey, thick cum filled Kaoruko from behind. As it sunk into the depths of her bowels, she felt her stomach growing warm. Her pussy was tingling, and her colon was being flooded with cum. She lightly came again as Tateo groped her ass, milking the last few drops from his dick. He stayed in her butt until his dick became soft. While he was softening, Susumu entered the room, with a frustrated look on his face and an erection that hadn’t gone down.
“Kaoruko, I see you’ve made our younger brother into a man,” said Susumu. “But my erection is still troublesome. I can’t go out like this.”
“Susu, you’re really big,” said Tateo. “Will I be like you when I grow up?”
“You have the genes of the Sazaki family. I have no doubt you will,” said Susumu, “But sex isn’t something you do in the butt. How could you ignore Kaoruko’s beautiful pink pussy?”
“Her butt’s bigger and softer. She squirted on me and my face smells like her pussy now,” said Tateo.
“Let your older brother show you how it’s done,” said Susumu. He sat on the couch, his dick sticking straight up. Kaoruko crawled over, mounting herself on her brother’s penis with ease. Tateo watched in awe as his sister’s pussy gobbled up his brother’s dick, the full length of his shaft vanishing inside her. His dick began to stir once again from seeing his sister get fucked.
“This is the real deal,” said Kaoruko. “It’s how you make babies. Susumu and I are careful to make sure that doesn’t happen. Because Sekai is the only one I want to impregnate me...”
“Don’t fantasize about him now, I’ll lose my erection,” said Susumu. “Kaoruko, get moving. My dick’s in its favorite place.”
Kaoruko bounced up and down on Susumu’s cock. She took it at a steady pace, pulling as far back as she could before slamming back down on his dick once again. With every thrust, her ass cheeks jiggled, her breasts bounced and her belly fat rippled. Her plump, curvy body shook like jelly, drawing Tateo back towards her again. He had recovered quickly, his dick hard with excitement. His sister’s butt was dripping with his cum, calling him back inside.
“Susu! I want to do Kaoru in her butt again while you take her pussy,” said Tateo.
“Kaoruko, can you handle two dicks inside you?” asked Susumu.
“I can handle anything my brothers throw at me,” said Kaoruko. She slapped her butt, grabbing one cheek and pulling it to the side to show off her cum-filled asshole. “My ass belongs to you, Tateo. Use it as you please.”
Seeing her puckering asshole, slick with his own semen, Tateo went back inside for a second helping. Gyanko was being pounded on both sides by two very different dicks. One thicker and more rugged, that reached her deepest parts. And one from the back that didn’t go very far up her ass, but was hard and moving very fast. To help himself get a better grip, Tateo reached around and grabbed onto his sister’s belly fat. Gyanko had plenty to grab. As her little brother’s fingers squeezed down on her warm paunch, she sighed happily.
“Grab it and play with it as much as you want,” said Kaoruko. “There’s more to love.”
“We can’t ignore your fat tits, either,” said Susumu. He picked up one of Gyanko’s breast and placed her erect nipple in his mouth, sucking on it hard to hold it. He kept thrusting inside her, making her other tit freely jiggle about. Beads of sweat were rolling down her body, the pungent stink of her body odor spreading outward from her armpits. The way her brother’s tongue rolled around her nipple, making and keeping it hard, was turning her on so much that her body was going numb.
“I love you guys,” said Kaoruko. “I have the best brothers in the world. Not even Kirara has a body like mine.”
“Kaoru, I want to have sex with you again!” said Tateo.
“You’ll have to wait your turn,” said Susumu.
“Boys, I can take both of you at the same time,” said Kaoruko. “What are you waiting for? Drain your balls inside me!”
Susumu and Tateo alternated their piston movements. When one of them slid inside Kaoruko, the other pulled back out. She bounced back and forth on their cocks, riding them as her lower body echoed with lewd squishing sounds. Tateo’s finger dug into her belly button, shaking her stomach fat around. When she leaned in closer to Susumu, he got harder from having her squishy belly press into him. Every part of her was screaming out to orgasm. Her clit was rock-hard and her thighs were coated in pussy juice.
“I’m cumming!” said Kaoruko.
Tateo and Susumu pushed their dicks deep inside her. Two hot spurts of cum coming from each direction filled her pussy and ass. A tender warmth filled her stomach as her bowels and her pussy were pumped full of fresh jizz, her brothers staying inside her until they were beginning to soften. Her body was dripping with sweat, and she could barely move her legs. Still resting on Susumu’s lap, her pussy squirted onto his waist, covering him in a sticky layer of her love juice.
“Let’s get you two cleaned up,” she said, tired.
Kaoruko was on her knees in the bathroom, once again. Susumu was standing next to her with a full erection, and she was working Tateo’s cock to get him hard. Kaoruko sucked Tateo’s balls, rolling his sack around inside her warm and sticky mouth. At the same time, she was giving Susumu a handjob, stroking his cock with careful, steady movements. It was their first time doing this as a family, and she knew they still weren’t empty.
“Kaoru, your nipples are hiding again,” said Tateo.
Pulling his balls out of her mouth, Kaoruko looked up at him. “They’ll come out when you play with them. For your last shot, you can cum on my boobs.”
“I want to see you covered in cum,” said Susumu. “It’s when you look the most beautiful.”
“You flatter me, but your dick still isn’t my ideal,” said Kaoruko. “Though I do love it very much.”
She placed Tateo’s glans near her nipple, along with Susumu’s. Tateo’s was smaller, and went part way inside her areola. She continued stroking them, rubbing them. As she moved her body about, her breasts swayed from side to side, sending drops of sweat flying about. Her pussy and ass were still dripping with cum. She would have to get it out in the toilet before stepping into the bath.
Their dicks were incredibly sensitive from cumming just a few minutes ago. Kaoruko kissed their tips, and they exploded. Drops of cum rolled down into her areolae before she pulled the dicks away from her breasts, continuing to play with them in her hands. Spunk landed on her stomach, where it fell into her belly button. It landed on her face, heading onto her lips and her cheeks. Tateo aimed his cock when she turned around, glazing her ass with cum. She was covered in it, and smelled like semen all over.
“There. You two are finally soft,” she said. “Now let’s take a bath. Together. It’s a Sazaki family tradition."