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Synchronized Heartbeats

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Rin sighed as he sipped on the spoonful of porridge he was in the middle of cooking for his sister. It wasn't often that Gou Matsuoka got sick. The last time she did was when she was caught outside during a storm and he and Sousuke had ventured to retrieve her. Once they did find her, she hadn't been crying out of fear like the time when their father had died. No, she'd curled up into a frozen ball of emptiness. It was as if the hard winds had tugged out any feelings from her small form. When they returned home, Mrs. Matsuoka had discovered Gou was running a high fever. It took a full day of effort to nurse Gou back to health. He and Sousuke had stayed by her side the entire time.

Chopping up slices of a fresh banana, Rin frowned to himself. How the hell did Gou get sick this time? He dropped the fruit slices into the steaming pot of porridge before turning the knob to dial down the heat. Too bad Mom is out for a business trip, Rin thought. He didn't mind taking care of his sister but he wasn't exactly the best caretaker for a sick person. Mrs. Matsuoka would be out for a few days so she'd left a note detailing instructions for Rin on what to do for Gou and give to her. Unfortunately, today was only day one of three. He glared at the burn on his index finger, recalling how he'd accidentally touched the side of the pot while heating it up. A stream of cold water had soothed the burn but it only left Rin aching to hit the pool. Maybe once Gou got better then they'd go to the pool and she could help time him.

Coincidentally, the timer went off, pulling Rin's attention away from his finger. Clicking the stove off, he did the same with the timer. After grabbing a tray, he balanced a glass of water, a bowl of fresh porridge, and a tablet of medicine.

Upon entering his sister's room, the first thing Rin noticed was the tangled sheets pushed to the bottom of the bed. The second thing he couldn't help but notice was the bright pink underwear without the cotton shorts he'd seen Gou wear earlier. The shorts were probably tangled somewhere in the mess of the blankets. The third thing he noticed was that Gou was shivering. Sweat glistened on her skin like a second skin. Why had she chosen to wear a tank top if she was in this condition? Her spaghetti straps bared too much of her clammy, pale skin. It didn't help that her top had ridden up dangerously high while she'd tossed and turned in her sleep. Rin's dark eyes lingered a bit too long on the dip of her hips which led to—Gou shuddered again. Immediately, Rin set the tray down on the bedside table to lay the back of his hand against his sister's cheek. She was still burning as hot as she was this morning.

"Nn, Onii-chan…" Gou's plump lips opened slightly to murmur for him. Her warm breath caressed the back of his hand and Rin wet his lips in response. Slowly, he let his hand reach for a thick strand of maroon hair that stuck to the corner of her lips. He gently pushed away the hair before cautiously touching the tip of his fingers to the bottom of her lip. Rin stared at the plump, soft edge as he traced it with the lightest touch of his thumb. Somewhere within him, a strange energy sparked in the pits of his stomach. He didn't realize he was leaning his face closer and closer to hers until he felt her warm breath fan into his mouth. With lightning speed, Rin pulled back. He silently stumbled away—almost knocking into the bedside table—as he tried to calm his pounding heart.

"Shit, what the hell was I doing?" Rin mumbled, brushing a hand through his maroon bangs.

"Mnn…" Gou hummed as if in answer. Her brow twitched and then deepened into a frown as she released another uncomfortable shudder of distress.

"Gou." Rin shook the bare shoulder of his sister once he recovered his breath. "Hey, Gou. Wake up, you need to eat."

His sister mumbled something incoherent before snuggling her face against his hand. Her eyes cracked open, however, when Rin started shaking her a bit harder. "Ah, Onii… chan?"

"I made you some porridge." Rin grabbed the desk chair from his sister's study table and dragged it over to the side of the bed. He reached for the bowl, cautiously feeling the sides of the ceramic for a second to feel the temperature. When he decided it was safe to hold, he held it out to Gou.

She considered him with a bleary expression. "Onii-chan? Onii-chan, when did you… get back from… um, Puerto Rico?"

Rin choked back a laugh at how delirious Gou was. She tended to be this way whenever she had a fever. Admittedly, he and Sousuke had quite some fun going along with her delusions the last time. "Gou, I got back from Australia a few days ago."

"I told you," Gou spoke with a whine she rarely used, "you can't swim all the way over here from Puerto Rico!"

Rin tipped a brow at her. "Yeah, okay, Gou. Just go and eat your food so you can get better."

"But I'm tired." She pouted.

"That's why you need to eat, so you won't be as tired." Rin's patience was starting to wear out now.

"But it's too hot! I'm… I'm too hot, Onii-chan." Gou grasped the edge of her thin yellow top and started to peel it off her sticky body. Rin's eyes slid over the flatness of her stomach, her belly button, noting the small ridge of her ribs as her top revealed more and more the higher she went. She moved agonizingly slowly. If Gou wasn't crazy sick then Rin would have thought she was purposefully teasing him. Finally, when her top peeled back to reveal the round edge of a bare breast, Rin snapped his hands towards Gou's wrists to keep her from going any further.

She's not wearing a bra, he realized.

"Let me…" Rin's mouth had gone dry at some point. It took incredible effort for him to drag his eyes away from the naked flesh of her curves but he managed to do so somehow. He met her burning stare as he swallowed hard for words. "Let me f-feed you. I-I'll even blow on it for you."

"Really?" Gou sat up straighter, letting her top fall back over her stomach until only an inch of skin bridged the gap between her top and the edge of her pink underwear.

"Yeah." Rin shifted in his seat. His pants felt tighter than when he had first walked in.

Taking a deep breath, he forced the energy pooling in his stomach to cool down. Then, he turned to the tray and picked up the ladle, spooning up some porridge. Gou watched his every movement as he drew the ladle before his mouth and blew on it as promised. Carefully, he raised the ladle to Gou's face for her to sip on it. She shook her head.

"No, Onii-chan, that's not how you do it." She said and leaned over to demonstrate. Rin's eyes flicked to her shoulder when her spaghetti straps fell down at the shift of movement. As she leaned closer to him, Rin tried to not be distracted by the cleavage at the edge of his sight.

"G-Gou?" Rin tried to scoot back but realized too late that her desk chair had no wheels.

"This is how you do it, Onii-chan." Gou whispered, keeping her hooded garnet eyes on his as she brought her lips close to the ladle—close to his own mouth—and blew on it. Her soft breath brushed his lips along with the porridge's steam. The heat of her had his pants tightening even more and he instinctively held the bowl over his lap to hide the evidence. She continued to blow on the food with their mouths dangerously close together. The ladle was the only thing keeping their faces apart by the spoon's width. Rin was so entranced that when Gou finally closed her mouth over the ladle and their lips brushed together, he almost dropped the utensil.

He could practically taste the saltiness of the porridge on his lips when Gou said, "Yummy," and her tongue darted out to lick around her mouth.

"It's—It's good?" Rin stuttered as he faced away from his sister to shovel more porridge. He brought the ladle to his mouth to blow on it again but this time he blew several times to ensure that it was cooled down enough. All the while, he couldn't keep his hand from trembling. "Well, it better be! I had to cook for myself back in Australia sometimes."

And that was it. She didn't lean over and blow in demonstration for him again. They sat in silence as Rin spoon fed her diligently. Spoonful by spoonful, the porridge was slowly eaten away. Finally, when the bowl had been cleared, Rin reached for the tablet of medicine sitting in the corner of the tray.

"Here, take the medicine and drink this glass of water. Then go to sleep." Rin instructed Gou, holding the tablet out to her.

"No." She turned her head away from the medicine held out to her face. A stubborn pout was already forming on her lips. "I hate the taste of medicine."

"Gou." Rin held in a sigh at his sister's childish streak. "You have to take the medicine for your fever. Besides, you're already eighteen—an adult. Put your big girl pants on and take the tablet already."

"It's too hot." Gou fanned at the sweat still coating her body. The hot porridge hadn't exactly been the best meal to cool her down. If anything, Gou was sweatier than ten minutes ago. At least she seems more energetic, Rin thought wryly. "Besides... it's too hot to put any pants on."

At that comment, Rin's gaze automatically dragged to the lower half of her body. He took in the smooth, creamy flesh of her slim legs stretched out on the bed. Then his attention focused on the pink underwear she wore. He hadn't noticed before but the garment was lined with an innocent white lace trimming. A tiny white bow drew Rin's attention to the center of Gou's underwear where her core—

"I'm so hot, Onii-chan." Gou murmured softly. Her hands crept south, sliding over the center of her underwear where she pushed her index and middle fingers in slightly. "Onii-chan, I-I'm so hot here."

"I know… I mean—" Rin gulped, "you're just trying to get out of taking your medicine, aren't you?"

But when Rin tore his eyes back to meet his sister's gaze, he only saw a mixture of confusion and heat. She was helplessly wanton, practically writhing on the bed before him begging for a release she didn't know she needed. He couldn't soothe the ache for her though. After all, he was her damn brother. He shouldn't even be looking at her as she is now. , Rin silently thought as he hungrily drank in the sight of Gou curling her fingers against her clothed pussy. He couldn't let himself touch her.

No. The thought itself was ludicrous! He was Rin Matsuoka and he was a damn talented swimmer who loved the water with every being of his body. The water understood Rin best and so did he in return. He couldn't kiss his sister—that brush of their lips earlier with the porridge didn't count! He couldn't imagine tasting the sweetness of her with his tongue. He couldn't let himself brace his hands against the insides of her thighs. He knew it was forbidden to stare at her perfect breasts for long let alone palm them and nip those erogenous buds. Worst of all, he could never ever touch Gou down there. Heaven punish him if he even found himself… inside of her. At that thought, Rin found himself imagining Gou caged in his arms and shrieking out of pleasure as he thrusted into her with wild abandon until—he blinked the vision away.

Shuddering from the strange sensations racking his body and pooling in his abdomen, Rin clenched his hands tightly. His nails bit into the skin of his palm. The pain gave him a reprieve of clarity although Rin still couldn't ignore the tingling in his belly. His voice was rough when he said, "Gou, please, just take your damn medicine."

"Will it…" Gou peered at him through her lashes with a shy look on her face, "will it relieve the ache… down there?"

"I-I don't know." Shit. He should've just answered 'yes' just so he could leave already and take care of himself before she noticed.

"Why do I feel so strange, Onii-chan?" Gou bent her legs so her knees were up. Her hand was given more space so she could rub herself down there freely. Rin wasn't sure where to look—at his sister masturbating right before him or at the wanton look in her bleary eyes.

"Gou," He whispered pleadingly, "you can't—I'm your brother and we—you're not supposed to be t-touching yourself like this in front of me. It's—it's the fever… you're not thinking straight."

"Then why do I feel… so much better when I'm touched down there?" Gou whimpered.

"Y-You'll feel completely better if you take the medicine." Rin forced himself to stare at the tablet he still held out to her. However, from the corner of his eye, he could still see the shift in movement as Gou continued rubbing her fingers desperately in the spot between her legs. Perhaps it was just his imagination but Rin felt the room become warmer to the point it was stifling. Gou's soft erratic breathing had Rin shifting uncomfortably in the chair at the tight sensation in his pants. Then he realized that he too was breathing harshly himself.

Stop, stop, stop, he begged himself. Whatever they were about to do, there was a line to it. There were boundaries that he and Gou, as family, couldn't afford to cross over. It was absolutely taboo to do so—not to mention fucking disgusting…. So, then WHY? Why did he want so badly to take his sister in his arms—to take her right then and there on her bed. Rin couldn't—they could never be like that together. He didn't have the right to love her as more than family unlike Haru and the other guys from the Iwatobi Swim club. Rin couldn't make love to her without them being shunned by everyone else. It was impossible to even dream of having children with his own sister. The child could be mutilated or, worse, society would treat Gou and the child as outcasts.

No, no, no, the thoughts raced in Rin's head. A brother wasn't supposed to stick his cock up his own sister's pussy-or even think of it! He wasn't supposed to think of having a child with his sister much less imagine getting her pregnant.

Rin let out a stream of curses in head. His innocent, sweet Gou… she deserved to be happy with the perfect family. But whenever Rin tried to think of another man at Gou's side, holding a child with her, Rin wanted to drown himself.

And then Rin froze in the chair as the realization washed over him.

He wasn't just lusting over Gou because he was a man with sexual urges.

He was lusting over Gou simply because he was in love with her. Out of all the different types of love known to mankind, incestual love was the absolute worst. Incest was fucking disgusting and wrong on all levels. Rin wasn't into incest, he'd say, but he was into his younger sister. He was deeply, and sickly, in love with Gou.

The shock felt like the ice cold water he'd accidentally dive into during the winter when the pool wasn't done heating up yet. It left him breathless and with no sense of direction. For a second, he tried to deny that which was the sad truth even as he drank in the sight of his sister touching herself with her little moans echoing sharply in his ears.

"Hnn—mmnnn!" The expression on his sister's face seemed to border more on pain rather than pleasure as she struggled to relieve the hot ache throbbing in her core.

"Gou," Rin leaned forward just an inch but stopped when he felt his own stiff length pressing against the ridges of his abs. He nearly choked out the words as he struggled to speak through the aching heat suffocating him, "Please, take the medicine."

"Then, Onii-chan," Gou's pants echoed in his ears, "you give me the medicine."

Something within Rin snapped and he automatically slipped the tablet in his mouth before taking a mouthful of the water from the glass. The bed creaked when he stood from the chair and placed a knee on the bed to lean over her. With Gou caged in his arms, Rin briefly flashed back to the vision he imagined of himself pistoning in and out of her. He blinked the image away to focus on the girl waiting expectantly.

He swore Gou held her breath as his face slowly drifted closer to hers. Then, when there was only less than an inch between them, Gou pushed herself up to close the distance between their lips.

For a second, it was awkward because Rin wasn't sure whether to just let all of the water fall into her awaiting mouth. But Gou remembered that he had her medicine and was smart enough to open herself up to him. He hadn't considered how difficult it would be to do this but Rin decided to let the water flow over to her at a steady pace so that she didn't choke. Then, he tentatively pushed his tongue out and brushed it against her own. She jolted in his arms at first but then relaxed when he cupped her chin reassuringly. The tablet passed over to her and he heard the faintest sound of her swallowing it with the water. Rin didn't stop there—though he was silently screaming to do so in his mind. Instead, he continued to stroke his tongue against Gou's—tasting the sweetness of the ripe banana she had eaten with the porridge. He felt reverberations when Gou hummed as she hugged her silky tongue with his in return.

The hot rush in his belly returned again but it settled into a burning heat between his legs that had Rin grabbing the nape of Gou's neck and angling her so that he could kiss her deeper. Her lips felt so soft that Rin was vaguely worried his sharp teeth would cut her. Not that he could stop anyways—or wanted to. He swallowed the soft, mewling sounds Gou released into his mouth as their lips slid against each other with a slickness.

His hands moved and he felt silky skin under both palms. Rin's body shuddered at the realization that he had somehow found his way between her legs and his length was poking out sharply and ready to penetrate but she was only wearing thin, pink panties for protection and—

"Nn! Onii-chan!" Gou broke their kiss with a gasp. A thick strand of saliva stuck to her chin as she looked down between them. Rin reluctantly followed her gaze and his body stilled with dread as he gaped at the way his hips were pressed tightly into Gou's and if they hadn't been wearing the thin clothing they still wore then he would have been inside her already.

The head of his length was already pushing past her folds. The tight heat of her insides enticed Rin to push even further and unite them finally, panties or no. A primal instinct deep within screamed at him to just prick this woman's fertile body with his cock—to fuck—or mate—whatever a man did with the supple body of the woman he loved.

Make love to her.

"Shit!" Rin quickly pushed away from her to sit back on his haunches. Doing so only gave Rin a better view of Gou stretched out before him with her legs spread apart to display a dark spot staining the center of her panties. With how he had pressed himself into her, her panties were slightly pushed into her crevice. It gave him an erotic display of the sides of her wet mound. The stain was so soaked that he could practically see right through the thin material. Rin hissed through ragged breaths, "I almost… Gou, why didn't you stop me?!"

"Because it felt so good when I felt your hot tip. I liked it when your hard... thing started poking into me, Onii-chan." Gou whispered. Her brows were furrowed slightly as if silently asking him, why did you stop?, and a puzzled look had settled in her dark ruby eyes. "I feel even more weird though. I don't think that medicine did much, Onii-chan. What if—what if it's not just a fever? What if there's something else wrong with me?"

"What… are you talking about?" Rin tried taking deep breaths to calm down but it only seemed to make his heart beat faster because he knew where this was going already. Something felt cool at the tip of his length and he knew it was the precum he'd been leaking—or was it from the wetness in her panties when he'd grinded their hips together? "Gou, there's—there's nothing wrong with you. It's the fever talking."

"Are you sure, Onii-chan? I'm feeling so strange.." Gou's eyes were pleading but her hand slid south until she was pressing a finger into herself with her panties still on. He caught something glistening at the apex of both her thighs whilst the dark spot on her underwear spread. The stirring of her fingers caused sticky, wet sounds as she said, "Mnn.. it feels really weird here, Onii-chan. Something—something must be wrong with me…. Could you.. check it for me?"

"What?" Rin's mouth went dry, though he still felt the lingering sensations of their deep kissing from earlier.

"Check this…" Gou suddenly shifted the bridge of her pink panties aside to reveal the flushed lips of her pussy. Her womanhood glistened with a sticky coating of arousal that left dewy drops clinging to some of her ruby curls. He couldn't tear his eyes away so he barely noticed Gou shudder under his piercing stare. "Could you check if.. there's anything wrong there?"

He couldn't believe it.

Gou was baring her most intimate spot to him and was practically begging for him to touch that sacred spot with his own hands. Was this really the fault of the fever?

Rin had always been too focused with swimming to bother with girls much. He'd never even taken a girl out on a date back in Australia due to his activities. Swimming was his life and the only love he knew. Sure, the other guys in the club had ogled women in bikinis on beach trips and had no shame in bringing their porn mags to practice. Rin, however, had always stayed in the pool after practice to finish working on techniques and other exercises.

But he couldn't ignore the selfish want he had for his sister. The seed of a forbidden love had been planted within him at some point. It blossomed uncontrollably in the pits of his stomach, evolving into an insatiable lust and desire for the woman spreading herself out for him right now. It was like he'd been deprived of a meal he'd craved his entire life and now it was right there for him to devour. To taste her flesh would be a sin, but to wrap his swollen cock in the silky heat of his sister's body would be the death of him.

Retribution would surely find him if he ever went past the point of no return.

But as Rin took in the sight of his sister stretched out before him, asking him to corrupt her with his touch, he found that he was starting to not give a fuck.

Rin had fallen too deeply in love with her—damn him. He had past the point of no return long ago.

"Are you sure?" Rin spoke in a raspy voice. He swallowed hard. "Is this really what you want Gou? What if, when you recover from your fever, you regret what we… did?"

"I'm sick," Gou answered with hooded eyes, "not psychotic, Onii-chan. I'm letting you do this because… I love you."

Those three words answered another question he'd been asking himself silently. He opened his mouth, "But what if—"

"Onii-chan, do you love me?"

"Yes." He answered back without thinking. That was a question he didn't have to ponder over.

"If you love me," Gou hooked her fingers onto her panties and slid them down her shapely legs. She tossed them to the floor without breaking eye contact with him, "then you'll take care of me… won't you?"

"…. Yes." Rin breathed.

Because he loved her.

And the entire world may come to hate him for the sin he was about to commit but it couldn't stop him from loving his little sister the way he did.

Rin leaned towards his sister's flushed pussy and reached out with trembling hands. Gou stiffened in anticipation when he hooked his fingers onto her swollen lips and gently pulled them apart, stretching her entrance open with a wet clicking sound. He brought his face closer for better inspection as he peered deeply into Gou's pussy. He wasn't sure what to expect honestly since this was his first time seeing a real girl's privates. It was basically a wet hole that looked barely wide enough for him to insert a few fingers in. How the hell did a guy's dick ever fit through?

Her walls were a flushed pink, almost blushing red as evidence of how aroused she was. They glistened with a milky wetness—the same wetness that lubricated her entrance. He could see a fresh wave of that wetness leaking out from somewhere deep within her while he memorized every detail of his sister's pussy. There was enough light in the bedroom for Rin to notice a thin layer of membrane with a small hole in it. It fluttered with every breath she took.

Is—is that her hymen? Rin wondered. He couldn't say he was familiar with the female anatomy. During his junior high, when the P.E. teacher had taken a day to teach the class some sex education, Rin had ditched with Sousuke to go swimming. He already knew the basics of how babies were made so it was pointless to know the details of the process. Stupid younger him. Now Rin was acting purely on instinct, letting the needs of his body guide him.

As Gou breathed, her walls quivered in response to even the slightest movement her body made. His face was close enough that he could easily smell his sister's arousal—something strangely citrusy and musky. Rin couldn't see so far into her since it only got darker the deeper he looked and he didn't want to stretch her open any further for fear he'd hurt her.

"Wow." Rin muttered and Gou mewled at the sensation of his breath hitting directly into her core. As if in reaction, her walls shook and shifted like they were trying to suck something in.

"Is—is there something wrong?" Gou's breathing was heavy. "Onii-chan, I—I feel something tingly! It got hotter!"

"Really?" Rin mumbled and he pulled a hand away to blindly search for something he'd left on the bedside table earlier. "Maybe Onii-chan should take your temperature then…"

"Eh?" Gou sounded genuinely puzzled. "Onii-chan, what are you—ah!"

She started to arch off the bed as she felt Rin begin pushing a long, thin object into her. He held her down in place, shushing her as he carefully slipped the seven inch thermometer through her folds. He'd bought it this morning and planned to use it to check her fever's progress later but he guessed he'd have to use it now. "Don't move or you could get hurt."

"It—it feels so good!" Gou sobbed into a pillow she'd grabbed onto to control herself.

The glass on the thermometer fogged up from the intense heat of Gou's insides. Rin was more amazed at just how tight she was. Even though the thermometer was about as thin as his finger, it didn't exactly slip into her so easily. Her walls were tight and well lubricated with arousal but he still had to push the thermometer inch by inch until there was only half an inch of space left for him to hold onto. When Rin tried to tug the instrument out of her sheath, he found just as much resistance. She seemed to clamp onto the thermometer as if her body refused to let it go. Halfway, he released the instrument and watched in amazement at how it was sucked back in slightly.

"Onii-chan," Gou's breasts heaved up and down with her pants, "what are you doing?"

"Onii-chan is taking your temperature. Be a good girl and wait a few minutes." Rin grabbed the thermometer and gently, but firmly, pushed it back into her, eliciting a low moan of pleasure. He thrusted the instrument in and out of his sister as fast as he dared to. His length throbbed in response to the small squelching sounds that squeaked out with each pump into her. Every time Rin pushed the thermometer all the way in until he could barely hold onto it, he made sure to flick at the bundle of nerves just by his fingers. He loved how Gou twitched helplessly each time.

"I can… I can—ngh—feel the tip of it rubbing me deep in there!" Gou curled her toes at the practice penetration. She brought a hand down to her belly and pressed against it. "It's like.. someone is s-stirring my insides but it feels so good!"

Her musky juices coated Rin's hand and the thermometer with a warm stickiness that he longed to lick off. His other hand pressed down on Gou's belly to keep her from thrusting her hips but Rin wanted to snatch the pillow Gou was biting into and toss it across the room because he didn't want her to suppress her moans.

"Gou." Rin's eyes fell to the sheets below her rear even as he continued penetrating her deeply with the thermometer. "You're making a mess of the bed.. it's getting dirty."

"Ahn! Ah—ah—then," She spoke in broken sentences while he repeatedly plunged into her as he waited for her answer, "maybe you should—AH!—help me c-clean it up—haah! Onii-chan!"

He suddenly flashed to a lesson from his religious studies class in Australia.

There was a story of Adam and Eve and they were the first man and woman to be made. They lived in the Garden of Eden, a paradise for them and the animals. In that garden was a silver-tongued snake who seduced Eve into biting the forbidden fruit—a blood red apple juicy with the universe's knowledge. Their Creator punished them with a curse of pain and suffering until the end of their mortal lives.

He slowly tugged the instrument out of his sister. Checking it with a glance, Rin found that her arousal coated the glass too thickly that he could barely make out a number through the layer of milky wetness. He tossed it aside since it'd lost its purpose and returned to the junction between Gou's legs. He reached out a finger to slide down his sister's wet slit from top to bottom and whispered, "Onii-chan will help clean you up."

Because Eve was pure, she was naïve and easily corrupted.

Gou was no Eve though. And Rin was not her Adam. But they were two souls stuck in the wrong bodies with their destinies entwined.

Rin faintly thought to himself that he must've been born tainted as he reached out anyways for the forbidden fruit to taste its sweetness.

"Uh! Onii—mmn!" Gou arched her back off the bed, fisting onto Rin's maroon locks as he licked a hot strip up her dripping slit. The juices spilling out of her swollen folds clung to his tongue as he lapped her up.

Holy fuck!

Her juices were like a mix of some kind of berry—sweet with the right amount of tart but also mildly tangy with a heady desire. Its flavor stuck to his tongue even when he swallowed it. Her body's essence left Rin feeling light-headed and somehow thirsty for more, as if he'd downed a shot of some alcohol that burned its flavor onto his taste buds.

"Does it… taste weird, Onii-chan?" Gou asked timidly, pressing the back of her hand against her mouth to quiet her whimpers.

Growling in response, Rin gripped her hips to tug her rear closer to his face. He dug his fingers into the soft flesh of her ass cheeks to hold her up as he laid an open-mouthed kiss against the flushed lips. Wet sounds clicked through the stifling air as Rin kissed her core with endearing passion. He heard Gou gasp and then cry out when he slipped his tongue past her slick folds. Rin breathed heavily against her entrance with her curls tickling his nose as he swirled his tongue within her, getting a taste of what her inner walls could offer him.

"Unh—Onii-chan!" Gou started to buck her hips beneath him but he held her down, rubbing his thumbs in soothing circles on her waist. "Onii-chan—yes!"

As he made thrusting motions into her core, a sick thought crept into Rin's mind: it would be even better if I could thrust my cock into her instead.

Rin stopped his ministrations as soon as the image popped in his head. Pulling back slightly, he took a deep breath to clear his mind. A sweet, shy voice called out to him in confusion and he fixed his attention onto Gou's face. Her cheeks were stained a scarlet red like the lips he'd been caressing with his own earlier. Maroon bangs sticky with sweat clung to the sides of her rosy face. Raising a hand tentatively, Rin brushed her bangs aside with heartbreaking gentleness. Rin's red eyes met a reflection of his own except they were filled with an eagerness to be satiated with the love only he could give her.

"Gou," Rin spoke in a strained voice, "do you trust your Onii-chan?"

"With all my heart." She answered with a dazed smile while brushing a hand lovingly through the silky locks of her brother's crimson hair.

"I… I don't know if I can hold myself back." Rin murmured, pressing light butterfly kisses all over the insides of her creamy thighs. He loved how he could make her body respond with small shudders and twitches at a whisper of a kiss.

"Then don't." Gou whispered. Before Rin knew what she was doing, her legs had wrapped around his waist and tugged his body against her form. She was caged in his arms but he was trapped tight between her legs. It took the phrase 'like-two-peas-in-a-pod' to a whole new level. "Don't hold back, Onii-chan. It's okay if you want to give me your everything."

"But if my everything isn't what's good for you?" Rin's voice broke at his own question.

Gou's eyes flicked across as she took in the vulnerable expression on her older brother's face. Rin glanced at her mouth when she licked her lips before answering with, "Then I guess I'll be sick in love with you forever, Onii-chan."

"Why is our love a sickness?" His lips gravitated closer to hers as they spoke. They were like a proton and neutron—a force that couldn't bear to be apart from each other.

"Because I am not supposed to feel this way towards you, Onii-chan." Gou sighed against his mouth when her bruised lips finally brushed against his. She reached between them and he growled into the corner of her mouth when she touched the solid tent in his black shorts. "And you're not supposed to feel this way towards me."

"Gou, not—" He tried not to choke over his words but, shit, her touch had him grasping the sheets by her head, "—not there!"

She took one of his hands and guided it to the spot between her legs, soaking with her juices and traces of his tongue's work. Gou uncurled his index and middle finger to slide them past the entrance and into her hot hole. Rin instinctively rubbed against her swollen clit, rolling the bundle of nerves with the pad of his thumb. Gou gasped, "An older brother isn't… supposed to be fingering his sister s-so deeply… like this—oh!"

"Gou—fuck!" Rin gritted his teeth as they fondled each other while gazing endlessly into the other's eyes which were practically mirror reflections.

"A little sister.. isn't supposed to be holding her own brother's d-dick in her hands." Gou panted and, without warning, she quickly tugged down the band of Rin's shorts. His erection bobbed in freedom before resting against the muscles of Rin's abs. His length was thick and engorged an angry red from arousal. Crystal clear precum spilled down the side of his shaft. A large bead of his arousal sat on the tip like a dew drop. "A sister isn't supposed to do this either." He hissed when Gou suddenly swiped a finger on the tip of his erection to pick up that fat bead of arousal.

"Don't—" He started but she was already popping that finger into her eager mouth. Her eyes fluttered closed as she savored his taste.

"Sweet." She hummed. Rin swore he caught surprise flash in her face but he was too aroused to bother. Her finger reached back down and lower and he saw white for a second when she grazed a nail against his sack which was heavy with excitement. She rubbed in between the cleft of his balls which quivered under her touch. "So this is where the formula is to make babies…."

Babies. The thought echoed in Rin's head as if his sister had just whispered the sinful thought right into his ear.

"Gou," Rin leaned into her neck and nibbled the soft skin there to distract himself from the thought and from fucking her on the spot, "I can't give you what you need."

"Yah!" She jolted under him when he bit too hard on her flesh. He licked the skin soothingly, stroking it in apology. "And—and what do you think I need, Onii-chan?"

A family who can love you properly. A brother who won't touch and taint his sister like this. Not me, Rin thought sadly. Instead, he replied, "To… to get better… from your fever."

"Then… help me get better, Onii-chan." Gou moaned breathlessly into his ear. Rin was too distracted with how his stomach clenched at the surge of pleasure Gou's moans sent straight to his cock. As if to agree with him, several fat drops of precum dribbled down his length. He didn't notice how Gou had locked her heels back around his waist and pushed him closer to her until he felt an incredibly soft, wet heat press against the base of his cock.

Swallowing back a groan, Rin relished the sensation of Gou's slick pussy grinding against the base of his cock. There was no protection between them as the bare hot skin of their sexes rubbed against each other. It would be so easy, so quick, for Rin to just angle his hips and impale her on himself. It took all of his strength to stop himself from doing just that. Instead, he distracted himself more by smashing his lips against Gou's, nibbling the plump edge of her mouth and sucking on the candy of her tongue for a whole minute. Their aching lips grazed against each other when he finally whispered, "No, Gou… don't ask me that. Fuck—you have no idea how much I want to… to be sheathed in your body and then make love to you so hard that you still won't be able to get out of bed once the fever passes but I… we—we don't even have any condoms."

Not to mention he was her brother.

"But Onii-chan I… I need it." She grinded their hips together to emphasize her point and he almost took her right there—fuck whatever rules and taboo crap. Gou continued to writhe beneath him even as Rin fought to control himself. "Onii-chan, I—I can't! I need it!"

"What, Gou?" Rin couldn't help but growl, rocking his hips against hers but not penetrating. "What do you need?"

"I don't know!" Gou cried out. Rin drank in her appearance as she squirmed under him. She looked desperate, wanton, and fucking sexy all at the same time with her ruby hair pooled around her head like fallen rose petals. She was biting her bruised lip in frustration because she was so damn innocent and didn't know what the hell to do. Rin's eyes drifted lower, past her bare shoulders that he'd kissed earlier, and fell to her swollen breasts. Her nipples pointed through the thin cotton of her yellow tank top. Her flat stomach was exposed since he'd pushed the hem up to get a better feel of her curves. At some point, he'd printed a scatter of angry kisses and bites across the surface of her belly.

"You don't know?" Rin grunted as he dipped his head down to suck a covered nipple into his mouth. Gou gasped and he reached a hand up to tug down the top of her clothing. With one breast fully exposed to him, Rin pressed a wet kiss onto the stiff rosy bud. Then he nipped at the peak, swirling his tongue around the areola every few bites, and ignored how Gou gripped at his hair tightly. Rin's hair tie had slipped off him at some point and his hair was shaggy enough to graze his shoulders.

"I want you!" She finally cried out.

"Where?" Rin asked while marking her bare breast with love bites. Her neck already bore an angry hickey from his earlier treatment.

"In—inside me, Onii-chan." Gou reached between them and stroked his length lovingly. Her fingers wrapped around his base and caressed him all the way from the bottom to the top. With each pump, Rin thought he would come in her hands right there, spurting himself all over her belly. Her hands pulled him closer and closer to releasing the ache in his groin. With the hot buzz rushing in his veins, he felt like he was standing over the edge of a cliff and staring down at a sea of water to catch him in its embrace.

In response, Rin uncovered her other breast and took the neglected nipple in between his teeth, tugging on it gently to draw out a hiss. While pumping him, she said quietly, "I want you inside of me… and thrusting your c-cock.. molding my insides to your shape."

Maybe his sister wasn't so damn innocent after all.

Or his touches had already corrupted her.

"No condom." Rin repeated with a tinge of disappointment in his voice. He gave the nipple one last hard suck and it released from his mouth with an audible pop before he started trailing wet kisses down the valley of her generous breasts.

"Then... just pull out before you ejaculate." She grinded their sexes against each other insistently and he nearly snarled in reaction.

"We can't risk it. You could still get… pregnant." Rin struggled to say that last word.

"I'm eighteen already and you're almost twenty." She tried to reason with him though it was hard for her to think clearly with him assaulting her breasts with his sharp teeth.

"We could still get in trouble." He mumbled against a stiff nipple, tracing the round curve of her breast with an index finger.

"Onii-chan, didn't you say you'd make me feel better?" A slight whine started to creep into Gou's voice. Rin groaned when he felt Gou toy with the head of his erection that'd been painfully engorged for however long they'd been like this. Somehow, he'd been able to keep himself from bursting all over Gou and her sheets. Unfortunately, a thick vein painfully throbbed at the side as evidence of the release that was sure to come somehow.

His sack felt heavy and ached with the need to relieve itself. It didn't help that Gou was rubbing her palm all over his head, massaging the thin pink membrane stretched over the tip and coating her hand with his precum. Bolts of pleasure racked through his body and built up in the pits of his stomach. A hot ache seared within his pelvis, threatening to drown him and wipe his mind clean of anything coherent. Her fingers tugged slightly at the layer of foreskin that had peeled back as his erection grew. Gou slid those fingers up the neck of his shaft only to trace the mushroom head of his tip and rub the cleft teasingly. She then held up her hand to show to Rin the mess he'd left on her. Once he got a good look, her tongue darted out to slurp up the gooey strands sticking to her palm and between her fingers. "You're as hard as a rock, Onii-chan—I know you want this as much as I do."

He was painfully hard as a fucking rock all right and it was what kept him rocking his hips against hers despite his efforts to stop. Instead, Rin rasped out, "I'll get by on my own… later."

"Onii-chan, just stick it in me. We don't have to thrust." Gou pleaded with him. She rocked her hips against his in answer and together they moved like synchronized divers. "I just want to feel you—no protection or fingers. I want to know what your bare skin feels like sliding within me. Please…"

"Won't it.. hurt for you?" He didn't have to ask if she's still a virgin because he already knew the answer. She'd always been more interested with swimmer's muscles rather than the swimmers themselves.

Gou cupped his cheek with one hand and caressed the taut muscles of his back with the other hand, murmuring, "Then be gentle with me."

Rin, in his opinion, was no gentle person. If anything, Rin was aggressive. In the pool, he clawed through pounds of water as he swam his way to victory. He wouldn't allow anything to slow him down on his path to success and damn him if he did. Even so, he was gentle as he covered Gou's hand with his. With both their hands wrapped around his enlarged, thick length, they guided it towards her entrance together. Gou sighed softly when his tip rubbed up and down her slit teasingly, spreading each other's juices. He smeared his precum all over her entrance just in case she needed more lubrication. They both hissed when he finally pushed forward and his bulbous tip began slipping through her swollen folds. She felt a delicious burn as her lips stretched open to welcome the thickness of him.

"Almost…" Gou panted once Rin's entire head poked past her folds. She had never felt so open, so spread apart before as her body continued stretching and straining to accommodate to the size of him. Her hands scrambled across the bed for some purchase—anything to hold onto as her body yielded to her brother's intrusion. They both took a moment to breathe and relish how gratifying the sexual penetration could be. Even though Rin was barely past her entrance, his tip was bathed with a lovely heat that warmed him from the thin membrane of his head to the aching pits of his stomach. When Gou started shifting beneath him, Rin took that as a sign to continue. His balls clenched out of delight as he pushed his cock farther into her in an agonizingly slow pace. He was amazed that he somehow didn't just ram himself straight into her despite how badly he wanted to. No, Gou was to be worshipped—body and soul with his love. It was a miracle she'd even chosen to love him the same way he did with her.

Rin didn't deserve her.

And he mumbled that thought aloud as he hit a soft, spongy barrier halfway through. His ruby eyes flew to hers and she stared back at him with a hooded gaze. Then, she nodded in answer. It was just the barest shift of her head but it was an answer nonetheless. Rin dipped his head forward and captured her lips with his own. Minding his sharp teeth, he crushed their mouths together aggressively, drawing out a surprised gasp from her. Gou only opened up to him even more and he caressed her tongue with gentle strokes. When Gou started mewling for air, Rin used that as a distraction and thrust his hips sharply into his sister's tightness.

"NGH!" Gou tried to twist her face away but Rin held her in place with a hard, open-mouthed kiss that swallowed her cries of pain. He felt a small rush of warmth squeeze past his cock and dribble down her slit in a scarlet river. Once Gou stopped shaking in his arms, Rin pulled back to study her face. Her eyes glistened with tears and when they started to spill over, he leaned down and licked those tears away. Drop by salty drop.

"Are you ok?" Rin whispered past the shocks of pleasure tightening within his abdomen. It was hard to think and Rin felt nearly dizzy with the happy buzz in his groin.

"Onii-chan," Gou gasped, "my—my hymen…"

"It's done." Rin breathed, pressing chaste kisses on her cheek, then her nose, then the corner of her mouth. "I broke through it. It's over."

"So you're—you're fully inside me?"

"Almost. A couple more inches to go…"

"Couple more inches?!" Gou's eyes widened in shock. "But I—I feel so full! You stretched my insides so much, Onii-chan!"

"I guess I'm a bit big." Rin couldn't help but smirk. It was hard for him to speak as his cock throbbed within her, begging him to start pounding away to relieve the ache.

"Onii-chan, your ego—ahn!" Gou yelped when Rin started to press into her again. Her walls stuck to him, massaging his hardness with a tight pressure. A sticky wetness coated his member but it still took effort for him as he slowly pushed through her tight heat. It was easy to slip through her entrance but the deeper he went, the tighter she got. It was like she was trying to push her brother out and suck him into her at the same time.

She feels like fucking heaven, Rin thought as his brain raced. It was like cold fire was blowing throughout his body, under his skin. The pressure tightened and rose, building into a crescendo as he finished sliding into her all the way home with his clenched sack resting against the slick skin of her rear.

Once he felt a spongy wall press against his tip and stop him there, he groaned out, "I'm in…"

"W-Wow. I can feel your hardness reaching me... all the way to.. here." She laid a hand right below her bellybutton and rubbed the spot where there was an evident bulge in her stomach. He swore he could feel the pressure tightening as she caressed the small lump.

Rin let out a sharp gasp when she suddenly pressed her hand down. Holy shit, he could actually feel her touching him!

"Oh, Onii-chan… you really stretched out my insides.." Gou gasped for air, continuing the rub the slight bulge in her stomach. With her heels locked around his waist, she began shifting their bodies together in small motions. "Ah! Ah—so good…"

"Gou," Rin growled, burying his face into her neck, "no thrusting.. r-remember?"

"You didn't say anything… about rocking—nn!mmnyes—Onii-chan!" She continued moving and the fire in Rin's body raged hotter with each rocking motion. "I—I can feel your cock… kissing my womb!"

"Nggh! Gou, stop! I can't—don't!" His cock swelled up even more and that was his only warning before the cold fire fizzling in Rin's groin exploded. He arched his back, unintentionally digging himself deeper into her as his mind blanked out. He vaguely felt his sack clench and relax in spasms as his orgasm drowned him in hot, electrifying waves of pleasure.

"Onii-hyan!" Gou cried out, arching off the bed until their bodies were curved flush against each other, sweaty skin pressing against sweaty skin. Her slick walls contracted, clamping onto Rin's cock tightly and squeezing him as his hot seed shot straight into her depths. He grunted at the faint sensation of Gou raking her nails across his back in desperation. "Onii—ngh—we're—making babies!"

Hot tingles echoed throughout Rin's body as the icy fire simmered down with each spasm that hit him. Breathing raggedly, he felt like he was back in the pool again, pushing through the sparkling clear water that caressed him like silk. He was on his last lap, drawing in desperate breaths of air while his muscles ached deliciously. Rin's head broke through the weight of the water—and he nearly stopped breathing as dread washed over him with the realization of what he'd done.

"Gou." He looked at his sister with wide, horrified eyes.

"Mmn, Onii-chan," She panted with her sweet mouth open, "you're.. still twitching in me."

"Gou." Shit, shit, shit, shit, shit! "I.. I came inside of you!"

"I could feel you squirting stuff within me.. burning your mark within." He was too numb to stop her as she wrapped a hand around the sweaty nape of his neck and pulled his face down to kiss him. "Your stuff was so hot, Onii-chan. My tummy… feels so full and warm… with your hot stuff."

"I came inside of you." Rin whispered against her lips but she continued kissing him with dazed yet satiated eyes. He didn't want to pull out just yet for fear of what he'd see.

"You injected your medicine into me, Onii-chan." Gou reached down to rub the bulge again with a hand. "Your medicine… yourself is inside me. I feel so much better now. That's good, Onii-chan, you made me better."

"No, Gou…" Rin choked out, trying to hold back a sob of frustration, "you—you don't know what you're saying! I'm your brother—your Onii-chan—and I just… shot my sperm into you! Your brother just shot a load of his sperm into your womb! I took advantage of you with your fever—I practically fucking raped you!"

"No, Onii-chan." Gou shook her head tiredly. "You injected me with your medicine.. to make me better."

"Shit, Gou!" Rin hissed through the uncomfortable burning in his throat but his sister's eyes were already fluttering close as she drifted to sleep. He studied her peaceful, satiated face for a moment longer and took a deep breath before slowly pulling his limp cock out of her. She quietly moaned in her sleep once his tip squeezed out of her soaking wet folds.

Rin sat back on his haunches and took in his work as his cock dripped a mixture of their juices and cum onto the sheets between them. Gou still had her legs bent and spread with Rin nestled in between. Her hands lay on the flat of her belly, covering some of the pattern of hickeys he'd given her. The globulous mounds of her breasts looked abused and tender, especially the peaks. Her face was still flushed and sweaty but Rin was slightly surprised to find that her complexion did look better somehow. Meanwhile, her entire body had a dewy rose color that shined with a thin layer of their sweat. The air was stifling with the heat of their lovemaking. A musky, salty-sweet scent clung to their bodies—especially their sexes.

Small movement caught his eye and Rin pulled his gaze back down to the spot between Gou's legs. A white glob of his semen was oozing out from her slit. He also noticed a film of white had been smeared across the lips, mixing with the blood that still stuck dry on her.

He should've felt disgusted with himself over how he'd tainted his sister inside and out.

Rin did.

He should've been scared shitless over what he'd done.

Rin did.

He should've felt ashamed and hateful of himself because he was her fucking brother and he just fucking dumped an entire load of his seed right into the depths of her womb.

Babies. The thought surfaced in his mind again.

Babies between a brother and sister.

Rin wanted to drown himself right then and there. There was no going back from this. And if something happened to Gou… if she got... then he was entirely to blame for cursing them. Nothing good could ever come from this sick love the Matsuoka siblings had for each other. It was terribly wrong for Rin to love his sister as anything more than family. Unfortunately, love was something that no one could control. Unfortunately, their love was forbidden. Blood and labels chained it—chained them—down. So, for all the guilt and hate that made Rin want to kill himself, he couldn't deny the hot pleasure that spiked through his core, stiffening his cock and making it rise again, as he drank in the sight of his sperm oozing out of his sister.

Instead of thrusting his cock back into Gou like his body was already aching to, or cleaning her up like he should have, Rin simply slipped off his ruined shorts and boxers. He then fixed Gou's tank top, laid himself beside her, and tugged the blanket over their mostly nude bodies. He continued to gaze at her beautiful, sweet face until night fell on them and his eyes reluctantly drooped shut.