Nathan and Shelli

ISTORY

Nathan heard them as soon as he walked in the door. "Oh God... oh God... Yes... Yes, yes... yeah, baby..."

His sister Shelli and her boyfriend Mark. It figured.

Their parents were away overnight. Shelli had warned Nathan that Mark would be coming over. He'd just hoped he'd be gone by the time he got home from work. No such luck.

"Oh yeah." That was Shelli's voice, low and raspy. "Keep it up, stud, keep it up..."

Nathan groaned, dropped his backpack on the floor, and made sure the door was locked. He got himself a soda and headed upstairs.

"Oh, baby." That was Mark, husky and urgent. "I'm gonna keep it up all night for you, baby. You're so fucking hot!"

He stopped halfway to his room. Damn it, they hadn't even closed the door all the way. He was about to walk past, but his feet wouldn't move all of a sudden. He stayed in the hall and leaned over to peer into Shelli's room.

Nathan's sister Shelli was two years older than him--22. She had long blond hair and she was on the swim team, so her shoulders and legs were tanned and muscular. Her boobs didn't look that big in the swimsuit she wore at meets, but whenever Nathan saw her in a bikini, he couldn't ignore the fact that his sister had nice tits, boobs that were straining to bounce freely.

And they were bouncing now. Shelli was on her hands and knees and Mark was behind her, slamming his cock into her pussy hard and fast, and Nathan could see his sister's tits swinging back and forth with each thrust as she moaned and shook with pleasure.

"Oh yeahhh," Shelli moaned. "Yes, yesss, God yes..."

Mark clutched Shelli's ass, grinning as he fucked her. His eyes werwide as he looked down at her body, and he was biting his lip to hold off from cumming a little longer. His back was sweaty, and hairy, and he looked as if all he could think about was fucking Shelli all night.

Disgusted, Nathan started to walk away.

Then Shelli turned her face toward the door. For a moment she looked confused, as if she'd forgotten where she was and everything around her except Mark's thrusting dick inside her. Then she blinked as she saw Nathan, her brother, watching her, and she smiled. She winked at him.

Nathan stared back at her, his mouth dry. Suddenly he felt his cock stiffen inside his boxers. He was hard--harder than he'd been in months, aching for attention. He stared at his sister, naked, getting pounded by her boyfriend, moments away from cumming, and smiling at him, and all he wanted was to yank his pants down and start jerking his own dick right there in the hallway. With Shelli watching.

Then Shelli was looking away, her head down, breathing hard as her body started shaking uncontrollably. "Oh God yes," she moaned. "Oh God yes--ahh! Yes! Yeah!"

Shelli was cumming, and Mark was too, his hips jerking as his cock started pumping into her pussy. He groaned softly, holding onto Shelli's hips, his dick firmly planted inside her as he leaned back and let his cum stream inside her.

Nathan staggered back before either of them could notice him. His cock was throbbing as he made his way silently to his room, closed the door, and pulled down his pants.

***

A half an hour later he heard Mark leave, and then he heard the shower in the bathroom down the hall. He was watching videos on his iPad in bed, trying not to feel too angry at his sister.

Shelli had a right to have sex, he supposed. This was the first time he'd actually witnessed it, although he'd always known she had boyfriends and they did more than kiss and cuddle. But what bother him was Mark. He'd only met the guy a few times, but he seemed like a dumb jock, someone who thought he was above everyone else because his family had money and he'd been on the football team in high school. Shelli could have better taste in boyfriends.

But there was nothing he could do about that. He heard the shower switch off and tried to forget all about his sister.

Then she knocked on the door. "Nate? Can I come in?"

Now what? "Yeah, sure."

Shelli opened the door. She was in a long pink T-shirt, barefoot, and he couldn't tell if she had anything on underneath it. She looked in. "Whatcha watching? Porn?"

"No." He scowled. He'd been watching porn a little while ago. To jack off. Seeing her now made him think about doing it again once she left. "Lord of the Rings stuff."

"Nerd." Shelli sat down on the edge of the bed. "You okay?"

"Yeah. Why wouldn't I be?" He couldn't help looking at the bottom edge of her T-shirt and wondering if she had panties on down there.

"Sorry you saw that. I guess Mark forgot to shut the door." She giggled.

Nathan rolled his eyes. "Great guy."

"Hey, don't be mad." She patted his foot. "He's no great brain, but he's got what every girl wants."

"A hairy back and an ego the size of a Cadillac?"

Shelli laughed. "Don't be jealous, Nate."

"Jealous? I'm not--" He stopped. "Just seems like you could do better than him."

"Maybe." She tickled his leg lightly. He jerked it away. "How much did you see?"

"Enough. Too much. I should have walked away right away. Sorry." He shrugged. "Your business, not mine."

"It's okay. I kind of liked it."

He looked up from his iPad. "What?"

She winked. "Come on. You never thought of it?"

"Thought of what?"

He was wearing a T-shirt and shorts. Her hand drifted up his leg. She winked at him. "Seeing me naked?"

"Uhh..." He couldn't think for a moment. Her fingers on his leg were sending his mind into other directions. Not to mention his cock. "You're my sister. But, I mean..." He took a deep breath top steady himself. "Yeah, you've got a great body. It was--nice."

Shelli rubbed his thigh. "Really?"

"Really! You're hot, all right? Sexy. If you weren't my sister--" He stopped.

Shelli looked up at him. "What?"

He looked away. "Nothing."

She smiled. "You know, he was fucking me, and I didn't think I was going to cum again, and then--" She gave him a shy look. "When I was looking at you, I came. It was good. Better than good. Better than before. Just--fucking good."

Nathan's cock was trembling. He reached for a blanket to cover his crotch, but suddenly Shelli's hand slid up inside his shorts, and her fingers were over his balls, brushing against his shaft.

"Is this good?" his sister whispered. She slid a finger up and down the underside of Nathan's prick.

"Y-yeah," he murmured, biting his lip. "But--but--"

"But what?" Now her hand was around his dick, just holding it, gently.

Nathan couldn't say anything. Was this really happening? Maybe he'd fallen asleep and was having some sick, perverted dream--

"Let me see it," Shelli said, tugging at his shorts. "I haven't seen it since we were--well, too young to know better. I want to see it." She pulled again.

Nathan groaned, then lifted his hips and helped her slide his shorts down. Shelli smiled widely as his cock sprang free, jutting up toward the ceiling in her hand. "Very nice," she said, rubbing it up and down. "Feels good."

"Yeah," he said. "Real good."

Shelli laughed. Then she leaned in, staring at it as if she'd never seen a penis before. "It got big. I remember--well, that was a long time ago. We're not kids anymore." She licked her lips.

"What--what are you doing?" They had to stop. But he didn't want her to. "What are you--"

"What do you. think, Nate?" Then Shelli opened her mouth and gave the shaft a quick lick with her tongue. He spasmed, spurting a little, and Shelli giggled. Then she bent forward and slipped his cock between her lips, giving it a squeeze at the base before she started to softly suck him.

"Ohhh," Nathan groaned as his sister's tongue swirled around his dick. "Oh God, Shell..." He bit his lip again, instinctively fighting the urge to cum immediately in her mouth, down her throat. He didn't believe this was happening, he didn't know why, he knew it was wrong, it made no sense. But he didn't want her to stop.

Shelli rubbed her hand up and down his shaft as she licked and sucked, her other hand on his balls. Nathan looked down at the top. Of her head and thought of her on her knees with Mark balls deep inside her. Did she suck Mark off too? Before she let him fuck her? How many guys--

He shook his head, trying to put it out of his mind. He didn't care about that right now. All he cared about was the pleasure running through his prick, the feeling of his sister's lips all over his rigid dick.

Shelli came up once for breath, and gazed up at him. "Did you cum already? Before I got here?"

"Yeah." He nodded. "But it wasn't--like this."

"I hope not." Shelli went down again, and Nate almost came right away but controlled it, grasping Shelli's shoulder and squeezing it hard. She yelped quietly and he let go, settling back on the mattress as his cock strained and throbbed, aching to cum.

Shelli hummed tunelessly, her lips vibrating again his skin, both hands on the base of his prick now, and suddenly Nathan knew he couldn't restrain himself much longer. "Oh God, I'm gonna cum, Shell, I'm gonna--gonna--" He threw his head back and then his cock started spurting, deep into his sister's mouth, pumping over and over again as she kept sucking and rubbing him until his legs were weak and his heart stopped pounding. "Ohh," he sighed.

Shelli giggled as she sat up, wiping her arm across her lips. She reached over for a bottle of water next to the bed and took a swig. "You like that?"

"Yeah." He grinned. "That was--yeah." Then he looked at her face. "But why?"

Shelli thought for a moment while looking at his cock. No long stiff, it was still good sized. "Are you a virgin?"

"What?" He'd had two girlfriends. And one handjob from a girl at a college party whose name he never knew. "No."

"Good. I'd feel--weird." She shrugged. "I don't know. I guess I always wanted to, for a long time, after you started growing up and--getting good looking. And guys like Mark--I don't know, he's okay but after it's over he usually just leaves or goes to sleep. You're just--always here."

"Well, I don't have anywhere to go." He reached over and awkwardly squeezed her shoulder. "Thanks, I guess."

She smiled and squeezed his hand. Then she reached up and rubbed his sweaty T-shirt. "Take off your shirt."

Nathan hesitated. "Take off yours?"

Shelli smiled. "Okay."

She sat up and started pulling her T-shirt up over her head. Nathan watched, his mouth dry, his heart beating faster again as his sister's tits popped into view--bigger than he expected, with stiff pink nipples, bouncing slightly as she tossed her shirt across the room. "Well?" She put her hands on her hips. "Come on, Nate."

He yanked his shirt off, fully naked for her. Shelli wore a pair of pink panties, and Nathan felt his cock started to stir.

Shelli sank down on the bed, pulling Nathan close to her. He could smell her body, the soap from her shower, a little of her perfume from earlier, and the subtle aroma of the moistness between her thighs.

He lifted a hand hesitantly. Shelli nodded. "Go ahead. Touch them."

Her boob felt warm and firm as he rubbed it softly. He leaned over and tickled it with his tongue, then started kissing her nipple and stroking her other tits as she sighed softly. "That's nice," she murmured, a hand on his shoulder.

He kept kissing her tits while his hand trailed down her body, over her smooth stomach, and then between her legs. Shelli stiffened and he stopped, afraid he'd done something wrong, but then she pressed his hand down on her mound and he slid a finger under her panties.

"Yeah," Shelli murmured as he teased her slit. "That's good, Nate. Do that."

He pushed her panties down and slipped two fingers into his sister's wet pussy. Shelli moaned, kicking her panties across the room, and pressed his head to her shoulder as her body trembled. "Oh, oh, oh... that's good, that's good..."

Nathan pulled his head up, a serious look on his face. Shelli stared at him. "What?"

He moved down her naked body until his face was between her thighs. Shelli watched him, biting her lip, then yelped as his tongue flicked out across her pussy lips. "Yes!" she cried out. "Yes, Nate, yes, yes..."

He pressed her lips against Shelli's pussy and started licking at her clit, his hands on her inner thighs, his tongue darting around as Shelli moaned and started to writhe around him. She pushed down on his neck, guiding him to the right spots where he went eagerly to work, determined to give her body all the pleasure he could.

Shelli moaned over and over, and Nathan felt his cock getting hard again. Her thighs tightened around his neck, then slipped down, and then got taut again as the waves of pleasure grew inside her.

Nathan grinned, then gasped as his sister dug her fingers into his shoulders. He reached around to grab her ass, and she lifted her hands as he squeezed her hard, drawing a yelp and then a gasp of her own as she pushed her hips up, pressing her pussy against his lips and his frantic tongue.

"Oh fuck, Nate!" Shelli moaned. "Do it, just do it, just... keep doing it! Yeah!" She laughed, running her hands through his hair. "Little brother... little brother..."

He had to come up to breathe, but when he did he drove two of his fingers into her slippery slit, bringing another yelp and then a long groan of lust. "Yes," she breathed. "Give it to me. Give it to me, make me cum, Nate, make me cum!"

He went down again, tongue and fingers together, and after a moment Shelli's body began to shake uncontrollably, her legs quivering around him, and she threw her hands back over her head as she gasped and moaned, finally crying out "Yeah!" as a spasm ran through her body. She shuddered, biting her lip, then sank back, breathing hard, flat on the bed as Nathan watched her relax/

Eventually she looked up. "Wow."

"You like that?" He smiled, licking his lips. He could taste her all over his face.

"I think you did." Shelli pointed.

Down between his legs, his cock was hard again. Throbbing and ready.

Nathan pulled Shelli's legs apart and looked at her. "You want to do this?"

Shelli nodded. "Yeah."

"Okay." He got on his knees and grasped Shelli's thighs, aiming his prick at her pussy.

This was crazy. Shelli was his sister--but sister or not, she was a woman, and that's all that mattered to his cock right now. He leaned down, easing his dick forward, and then drove it deep inside her.

Nathan groaned as his cock slid in. Shelli's pussy was slick and warm, and his dick surged as he started thrusting into her, slow but steady, hard and firm.

"Yes!" Shelli shouted. She gazed up into her brother's face, a smile of pure joy across her lips and a glow of sinful lust in her eyes. She reached up to put her hands on his shoulders, and lifted her legs to wrap around his waist. "Yes, Nate, yes, yes..."

Nathan started thrusting faster, pounding his dick inside his sister's pussy, watching her tits wobble with each hard thrust. An hour ago he'd been watching her get fucked by her boyfriend--now he was inside her, his cock ramming her, his sweat dripping down on her chest, close to cumming, and he couldn't believe it. He didn't care. Shelli was his sister but she wanted his cock and that was all that mattered.

Shelli squeezed Nathan's arms, panting as his prick hammered her pussy, back and forth, hard and deep, filling her with mounting ecstasy as every second passed. She murmured his name, but after a few moments she could only grunt and moan, closing her eyes and giving herself up to the sensations coursing through her naked body as her brother fucked her, fucked her, fucked her--

"Oh!" Shelli shouted. "Yes! Yes Nate! Yes yes yes..." She pounded the mattress with one fist as she started to cum, letting her body surrender to Nathan's driving, insistent cock.

Nathan felt his sister start to cum, and he delivered one last hard thrust before letting his cock go and spurt into her pussy, his body shaking as his dick pulsed over and over again, shooting his sperm deep inside her as he watched her eyes flutter and her bare shoulders squirm.

"Ohh..." Shelli murmured, stroking his back. "Oh, Nate, that was so good. How did my little brother get so good?"

He eased his cock free of her pussy and sank down next to her. "It's easy when you really love someone."

"That's nice." She kissed his chest. "Next time I want to be on top."

Next time? He hadn't expected anything more than this--one crazy night that would never happen again. He patted her leg. "Anything you want."

"Yeah." She smiled and closed her eyes. Nathan watched her until she fell asleep.