The Fill In

Matthew sat on the couch, quietly flipping through channels on the TV. His little sister, Penelope, was scrolling through her phone on a website that Matthew didn't recognize. Both siblings were home alone, bored out of their minds. Their parents were out of town for a few days giving them nothing but time with each other. Matthew kept trying to look over Penelope's slender shoulder to see what she was doing.

Matthew's eyes widened when he saw what his sister was looking at. It was a picture of Penelope with the bottom of her shirt hiked up her slim body and held up with her chin. Her pale and perky breasts were out and exposed to sunlight, giving a perfect view of her pretty pink nipples. She was making a kissy face into the camera.

"Are you sending nudes?" Matthew asked, scaring Penelope.

"No." Penelope swatted at Matthew's arm.

"Then what are you looking at?"

"It's none of your business." Penelope said with her usual snark. She quickly closed the tab on her phone, placed it on the coffee table, and brushed a lock of blonde hair from her pretty face.

"It is my business. You're my sister."

"Do you really want to know? It's not something you're gonna like."

"Say it."

"It's porn." Penelope said. Matthew's eyes widened. He crossed his legs to hide his growing erection. Penelope snorted.

"I made an Onlyfans a while ago because, well, remember Eva?" Penelope began. Matthew swallowed and nodded. How could he forget about her? Eva Ramirez was the talk of Clovis High. She was only eighteen at the time, but her body oozed pure sex. The young girl was blessed with wide hips and a very generous bust, and she was tall. 5 '10 inches tall.

Matthew was twenty-one and Penelope was twenty. They went to the same school and they both crushed on Eva. Penelope was her friend (sometimes with benefits) and Matthew was one of the many boys who fantasized about her.

"What about her?"

"She started one." Penelope smirked.

"She did?" Matthew nearly jumped out of the chair. While he wasn't going to admit it, he was still thinking about Penelope's bare chest. He was sneaking glances at her lily-white low-cut tank top when she'd break eye contact. Even though Eva was the fuel for his horny teenage fantasies, he saw Penelope every day. Not in a sexual way obviously, at least not until a few minutes ago.

"Yup, anyway we were talking, and she brought up how much money she made." Penelope paused. Matthew hated it when she paused. It was just her way of making sure the person she was speaking to was still interested.

"How much?"

"Enough to move out of her parents' house."

"In this economy?"

"Yup."

"So you thought you'd do the same?"

"I am doing the same."

"You don't look like Eva." Matthew immediately regretted his words.

"Thanks," Penelope frowned.

"That's not what I meant."

"I know what you meant. If you plan on jerking off to her stuff, I'll send you a link. She's got a free non-nude page since you don't have a job." Penelope teased.

"Look who's talking. How much money do you make anyway?"

"None of your business is how much I make."

"So, you're not making nearly as much as Eva." Matthew said. Both siblings had a tendency to bite back.

"That's because I haven't taken any dick."

"Don't you have a boyfriend? That guy that mom hated who always wore sunglasses indoors?"

"Ricky? We broke up. Actually, we weren't even really dating."

"So why was he around?"

"Drugs, big brother. Use that big brain of yours and stop thinking about my tits." Penelope said. Matthew's face was beet red.

"I wasn't..."

"Then why do you keep looking at them?" Penelope asked while intentionally pressing her arms against the sides of her breasts. Penelope's perfect pale cleavage was on full display.

"Because I just saw them and we're talking about Eva. Like I said you're no Eva."

"If you like Eva so much then why didn't you go for her in high school?" Penelope crossed her arms over her chest, refusing to give her brother a show.

"Because... um..." Matthew stumbled over his words. Something you should never do around Penelope Wells.

"Because you're a pussy? Because you'd much rather jerk off to her than grow some nuts?" Penelope crawled into Matthew's face and stared straight into his eyes.

"Um..." Once again, Matthew stumbled. Penelope's braless tits swayed beneath the fabric of her top. He noticed her nipples brushing against the cloth. He felt her warmth near his skin. But most importantly, her knee was right next to his hard cock.

"Or is it because you like me more?" Penelope's judgmental tone dropped to a softer, more pleading one. Like she wanted a confession out of her brother. Matthew, despite his weakening willpower, wasn't going to give her one.

"Nope. You're my sister. I've seen you in bikinis. Your little low-budget porn pics don't get me going." Matthew was only half lying. Penelope smirked devilishly and backed up. Her slender back was resting on the arm of the couch. She spread her spindly legs, so her right leg was above the couch and her left leg nearly touched the coffee table next to it. She was wearing a pair of dark blue cloth shorts that left little to the imagination.

"So, you were only thinking about Eva?" Penelope added a slight purr to her voice as she played with the spaghetti strap of her top.

"Yup," Matthew said.

"So, if I took my shirt off right now, you wouldn't get hard? You'd still be thinking about Eva? The girl of your dreams that you talked to maybe twice over the years?"

"We were in Mr. Schmidt's class together." Matthew retorted.

"Yeah, and she was all the way up front while you sat in the back."

"Shut up." Matthew spat.

"Let me tell you something about Eva," Penelope slid her finger beneath the space between the top of her shorts and the bottom of her top, before sliding it up to the middle of her stomach.

"Senior year. I ate her pussy and played with her tits. She tasted fucking amazing. Do you know how big her tits are?" Penelope asked. Matthew nodded slowly while wiping away a bead of sweat that fell down his brow.

"They were more than a handful. Huge fucking milkers and they were all mine. I sucked on those caramel funbags for hours. You know what the best part was?" Penelope had lowered both of the straps of her top down her shoulders, teasing the top of her breasts. Her chest rose and fell rapidly.

"What?" Matthew's voice was barely a whisper. It took everything for him to not uncross his legs and jerk himself off. That meant Penelope would win.

"I was her first. Not her first woman. Her first time, ever. I made her cum. I made the perfect princess of Clovis High cum three times in one night with my hands and tongue. You know what makes all of this even better?" Penelope's hands slinked down her pants. Matthew didn't need X-ray vision to see what his own sister was doing to herself right in front of him.

"What?" Matthew asked after clearing his throat. Penelope was the most beautiful woman in the world right now. He wanted her. He needed her.

"She started her Onlyfans because of me. As far as I know I'm the only girl that she's been with. I've purchased her stuff. She's taken some... some big fat dicks, but that's it. As far as I know I'm the only woman she's been with- oof..." Penelope's small orgasm cut her off. Matthew's cock was throbbing so fast it felt like it was going to come to life.

Penelope slowly pulled her hands out of her pants. Her fingers were glistening with her own juices. She slipped them into her mouth and slowly licked her own girl-cum off her fingers. Her eyes were low and sexy, but she maintained eye contact with her brother.

"Now you might be thinking, why am I saying all this?" Penelope wiped her saliva-coated fingers over her stomach, leaving a wet trail along her toned tummy.

"It's because Eva doesn't have a boyfriend. The guys she's fucking are called Fill Ins. Their jobs are to fuck the girl and last long enough for the video. I don't know how she gets her hands on these guys, so I was thinking..." Penelope paused. An unbearable pause. Matthew's eyes were glued to the tiny droplet of her own juice dribbling down her chin.

"Say it." Matthew begged.

"Eva's made serious fucking money using these guys. Pictures of my tits aren't going to cut it. I need some dick. I haven't gotten any since... I can't remember. I need some dick on camera. I need you." Penelope smirked.

"I... Penelope you're... my...sis-"

"If you didn't want me, you'd have stormed off upstairs and touched yourself to Eva. You're still here. I'm not forcing you to do anything. Actually, you can leave whenever you want." Matthew was focused on his sister's face and the wet spot in her pants. This was borderline torture. No sane human being would pass this up.

"Penelope..." Matthew felt his brain scrambling in every direction. Obviously, the primal part of his brain told him he had a hot woman who wanted to shoot a porno with him. The sensible part of his brain told him it was wrong. He couldn't have sex with his own flesh and blood sister. His baby sister. No matter how hot she was. No matter how good her lithe body would feel in his hands. No matter how long it had been since he'd had sex.

"Also," Penelope began rubbing her nipples through her shirt. "One of Eva's Fill Ins? I'm ninety percent sure it was her cousin. You remember Danny? Tall and dark with wavy hair? I went to her pool party and saw the outline of his cock. Long and curved. You know what the cock looked like in her video? Long and curved. So your little moral dilemma is pointless."

"Not every cock looks the same..." Matthew said. Penelope rolled her eyes.

"Yeah, I know you're not in the big boys club." Penelope teased.

"How would you know?" Matthew couldn't believe he was letting Penelope get under her skin.

"Really? You've got more than three inches?"

"Shut up."

"You refuse to prove me wrong." Penelope said. Her left tit was out, and she was rolling her finger around her areola.

"Fine," Matthew uncrossed his legs, grabbed the waistband of his shorts, and slipped them down to his calves. His thick and meaty cock was flat against his inner thigh. Penelope's eyes shot straight down. She bit her bottom lip and pinched her left nipple.

"That's what I'm talking about, Matty... All I had to do was talk about your manhood and now we're flashing each other. It's so easy to get you frustrated. It'll probably be even easier to make you cum." Penelope's voice was nearly as thick as her brother's cock. Both siblings' mouths watered at the sight of each other's raw flesh.

"You talk too much, little cocktease." Matthew growled.

"You're too pussy to do anything about it." Penelope spat back.

"Get a real job, slut." Matthew's hand dropped to his thick cock. He was slowly rubbing the base of his meat as Penelope rubbed her tits.

"Tell you what," Penelope grabbed her phone, propped it up against the round coaster holder, and opened the camera app. "If you can fuck me good and make a decent video, I'll give you half of my earnings for the next four months."

"Make it six..." Matthew said.

"I'll make it eight if you can use that big dick properly."

"Don't worry about that." Matthew slipped his shirt over his head and slipped out of his shorts, leaving him completely nude on the couch. Penelope removed her shorts and panties, revealing her tight ass, long legs, and dripping wet pussy. Matthew stared at it. It had a small strip of blonde pubic hair like an exclamation point. Her lips were red and slightly swollen, but still nice and neat.

"No kissing on camera. No admission of love. I'm going to suck your cock and you'll fuck me." Penelope commanded.

"Where do I finish?" Matthew asked.

"Don't know. You'll figure it out when you feel it. If you can pass the blowjob." Penelope removed her shirt and reached out to hit the record button. Matthew froze up for a few seconds as Penelope leaned down and grabbed the base of his thick log. His heavy nuts rested in her soft palm as she began running her tongue around the veins.

She slowly licked the base of his cock like an envelope until she ran her tongue to the purpled head. Penelope let out a low moan when her lips wrapped around the bulbous tip. Her tongue slipped over Mathew's piss hole, and she pushed herself lower by loosening her jaw and lips.

Penelope wouldn't tell her brother how good he tasted. She definitely wasn't going to admit how turned-on she was even though her pussy juices were staining the couch. Matthew threw his head back and let out a deep, masculine groan that rippled throughout Penelope's body.

Thick male skin and saliva were the only things Penelope could taste. She closed her eyes as she lubed up the rest of his dick with her spit. Penelope's hand was still caressing Matthew's balls when she felt her warm spit hit her hands. Penelope tried to hold back the gag she knew was coming.

"Glrk!" She failed. Her brother was just too long and thick. She didn't want to look like some slut with messy hair and nothing but legs. Deep down she really did want to pleasure her brother, despite the constant teasing and insults.

Matthew's masculine pride shot through the roof when Penelope pulled back slightly from his beastly cock. Penelope's brows furrowed in frustration when she felt Matthew's hand brushing the back of her head. She pulled her mouth off his cock quickly, leaving multiple trails of thick spit that stuck to her plump lips.

"Too lovey dovey," Penelope whispered and shook her head.

"Sorry," Matthew whispered back when Penelope shoved his cock back into her mouth. Penelope pumped up and down along Matthew's thick shaft as she moved both hands to the untouched base. She wrapped her hands and ran them up and down his meat, sucking and slobbering like a pro.

"Fuck..." Matthew covered his mouth with his hand. Penelope smiled around his thickness (at least she tried to) when she heard him moan. Spit caked her palms as her long blonde locks tickled Matthew's stomach and thighs. Penelope worked her brother's log hard and fast, determined to make him moan again.

Matthew's butt raised off the couch a couple of inches, jamming his cock into Penelope's throat. Penelope gagged and spat again, sending a shotgun blast of slime all over Matthew's legs. Ropes and ropes of cum soaked Matthew's hairy nuts as Penelope continued to bob and slurp.

Matthew dropped back down and sank deeper into the cushion of the couch. Penelope's masterclass blowjob was sapping her brother's energy. Matthew's fingers gripped Penelope's hair, inadvertently pushing her farther down the base of his soaked cock.

"Glahk! Ohmmm!" Penelope's was a mumbling mess. She was addicted to the meat that plundered her mouth, but she really wanted to feel it inside of her. Penelope continued to suck for about half a minute before tapping Matthew's thighs, giving him the signal to stop.

Penelope slipped her dribbly mouth off her brother's cock and sat up straight. She felt the puddle she'd made on the couch on her ass. Matthew grabbed Penelope's bony shoulders and pushed her to her back. Their sweaty foreheads touched when they looked down to see the taboo act they were about to perform.

"You ready, cocktease?" Matthew whispered. Penelope gave her brother a nervous smile.

"Bring it, bitch." Penelope whispered back when she felt the head of her brother's cock brush her pussy lips.

Matthew worked his dick inside of his little sister slow and steady. Penelope relaxed her body and wrapped her arms around Matthew's wide back. Despite her request for no intimacy, Penelope found it impossible to stick with it due to the objectively romantic position her brother had placed her in. Matthew watched Penelope carefully as he slid himself inside her tight snatch.

"Eep!" Penelope winced when Matthew made it a quarter of the way. Matthew then slipped out of her, teasing her entrance with his sensitive head. They went on like this for some time. Every time Penelope shook or squealed, Matthew would slip his cock out.

"Stop... stop fucking teasing me... shithead..." Penelope's face was bright red and Matthew could tell she was faking her courage. His dark eyes stared her down as he pushed himself all the way inside as best as he could without hurting her.

Penelope felt like a hydro flask was stuffed inside of her cunt. A loud squeal escaped her lips until her breath got caught in her throat. Penelope's toes curled and her hips spread, giving her brother more space to shove himself inside of her. Matthew let out a sigh and Penelope's head snapped up.

Matthew was balls deep inside of his little sister on camera.

Both siblings lay still for a minute. Both of them sucked in the shared air and felt the heat of each other's bodies. Penelope's pussy squeezed Matthew's cock when it twitched back to life inside of her. Penelope never felt something this big inside of her. Ever. Matthew lifted his body up and pushed himself back into his little sister's tight pussy.

"Fuck!" Penelope screamed. It felt like a tiny person was inside of her, smashing her with a baseball bat. All of Matthew's weight crashed into Penelope and her guts were rearranged. Matthew moved his hips in a steady motion, just fast enough to make Penelope melt, but slow enough to not bust instantly.

"Fuck me big brother... fuck me like a slut..." Penelope whispered. Her snobby act crumbled to dust when Matthew pounded her. Penelope didn't care anymore. If strip teasing and mean words got her this much pleasure from Matthew, she'd screw with him for the rest of her life.

Matthew's heart pounded in his chest and sweat fell into his eye. Matthew didn't stop pounding her. His fingers were wrapped around her waist, digging into the soft and sweaty flesh. Matthew wasn't fucking her pussy, he was banging her entire body.

"Yes... YES!" Penelope screamed. Her pussy squeezed and gushed around Matthew's cock nice and tight. Every slam from Matthew was like a lightning strike that sent her entire body into overdrive. If Penelope's arms and legs weren't gripping her brother's back, she'd have fallen off the couch from the pure force of Matthew's fucking.

"Matty..." Penelope whimpered. She hadn't called her brother that name in a long time. This was more than sex to Penelope. This was beyond a casual fuck. This was beyond money or making a statement. This was something Penelope couldn't really comprehend.

"Come again," Matthew teased, a sly smile crossing his sweaty face. "Come all over your brother's cock." Penelope was high on sex and the moment Matthew spoke, she let out a big and loud sob of pleasure as she came. It was like Matthew knew what made her moan and writhe in his arms.

Penelope didn't feel Matthew pull out. She didn't notice him flipping her over to her stomach until she felt her face resting against the sweat-covered arm of the couch.

"Matty... you're going to split me in half..." Penelope mumbled. Matthew forced his dick between her thighs, shoving his thickness into her gushing cunt once more.

Matthew's hands clasped Penelope's buttery soft asscheeks. Matthew's right hand gripped her buns and his left pressed into the small of her back, pushing her even deeper into the couch.

Penelope couldn't even think about moving. Her original plan was to wear Matthew down until he finished. A quick video with her brother. Now Penelope didn't want this to end. Penelope would give her brother all the money in the world if he could keep this up. Matthew pressed his body into Penelope's plump ass, driving his dick deep inside of her over and over again.

"Ugh..." Penelope's groan sent a wad of spit down her chin. Matthew slowed his thrusts, gently grinding and rolling his hips. Penelope felt everything shake and bounce. It felt like her brother's cock was literally shaking the world around her.