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Unexpected (a Pinecest story)	By : Edward_or_Ford Category: +G through L > Gravity Falls Views: 18898 -:- Recommendations : 0 -:- Currently Reading : 0
Disclaimer: I do not own Gravity Falls or its characters. I will not earn any money from this story.

Chapter List
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Autumn 2013
“Help me set this up, Dipper!” Mabel demanded cheerfully, flopping forward onto Dipper’s bed while holding her new laptop, an early Christmas gift from their parents a few days before.
Dipper was bouncing lightly from the impact of Mabel’s weight on his mattress, and glanced up with a small smirk from beside her on his bed. He was sitting up with his back against the headboard, reading a novel. “Once again, you need the assistance of the resident computer geek, huh? Maybe you need to pay for a support contract?”
“Aw, you have to help me, Dip!” Mabel shot back in a fake whine. She rolled over towards him onto her back, her head coming to rest in his lap. Her upside-down face gazed pleadingly up into Dipper’s, eyes huge and bottom lip thrust out pathetically.
The smirk on Dipper’s face widened and he rolled his eyes. “Hopeless!” he taunted.
“As hopeless as you when you had a rip in the crotch of your pants last week, and you needed me to sew it up?” she replied sweetly.
Dipper closed his eyes in mock resignation and set his book aside. “All right!” he huffed.
Mabel squealed and flipped over, wrapping her arms around Dipper’s waist and squeezing, while Dipper rested his arm across her shoulders and affectionately stroked her hair with his other hand. She happily tilted her head up to look at his face, and he smiled back at her.
For the last few months, the twins’ close bond had grown even closer. To an outside observer, the playful banter and close physical contact between them could have looked almost flirtatious, and in a way it was. The love and attraction both twins felt for the other was stronger than ever, but they tempered their actions just enough that their un-sibling-like feelings weren’t blatantly obvious to see. They just came across as oddly close. Individually, they enjoyed thinking about being more than brother and sister to each other, unintentionally managing to make each other feel very desirable and aroused.
On the same wavelength, they both broke the embrace at the exact moment they thought it might be getting too weird for the other. “So, what’s wrong?” Dipper asked, now fairly well practiced in the flow of their evolving relationship dynamic.
Mabel also pulled herself back together smoothly. “Dad says I can use this ‘HBO GO’ thing on my laptop. So I can, you know, call up whatever I want, instead of just … whatever’s on!” Dipper snorted at Mabel’s terminology, resulting in Mabel lightly punching Dipper in the stomach. Quickly Dipper had the settings configured, then sat back with his book as Mabel started scrolling through the back catalog of TV shows and movies that were available.
“Man, there’s some stuff on here that lil ‘ol innocent me shouldn’t be watching!” Mabel giggled.
Dipper perked up at that. “Like what?”
Mabel gestured at the screen. “Like ‘Game of Thrones’, for starters! From what I’ve heard, it should be called ‘Blood and Boobs!’ Have you ever heard what it’s about?”
“No,” Dipper lied. He actually knew exactly what it was about, and in fact had secretly read all of the “Song of Ice and Fire” novels the show was based on. “How did you hear about what the show is like?”
“Wendy told me a bit about it our first summer up north, but I really don’t know very much about the story. She and her crew would sometimes watch it at Thompson’s place,” Mabel replied. Her expression turned sneaky. “Wanna watch an episode now?”
Dipper was torn. He was curious to see if the television adaptation was as good as everyone said it was. But he had to be careful. They couldn’t get caught by their parents watching this, and he’d also have to keep up the lie to Mabel that he didn’t know anything about it. In addition, he was very aware of two characters in the books named Jamie and Cersei Lannister, a pair of twins. Seeing how they would be depicted, while watching with Mabel beside him, could be exciting, or really mortifying.
He decided to take a chance. “OK, do it. I’m making sure Mom or Dad don’t see,” he said as he got up to close his bedroom door.
Mabel started the first episode of the first season, the twins watching on the laptop while lying on their stomachs side by side on the bed. Sure enough, there was plenty of graphic gore and gratuitous nudity. Dipper squirmed with embarrassment at watching this with Mabel, but he didn’t want to stop either.
As the episode drew to a close, the character Bran was overhearing sounds of passion through an open window, and Dipper knew what was coming. Sure enough, the Lannister twins were revealed as the source of the noises, with Jaime taking his sister from behind
“And THERE’S the incest!” Mabel cried with mischief.
Dipper jumped, gaping at Mabel in disbelief as she paused the playback. “Oh come on, Dipper! Everyone knows the twins on this show are gettin it on!” she teased. “And so did you! I’ve seen those paperbacks under your bed! You knew exactly what was going to happen!”
“Sorry,” Dipper said sheepishly, blushing. “But it’s a little … weird, I guess.”
Mabel’s cheeks also darkened. “I think we can handle a little weird,” Mabel replied, and Dipper swore her eyes twinkled. He returned the expression without thinking.
With that, Mabel grinned and unpaused the video. The show quickly concluded, and without hesitation they decided to call up the next episode.
Winter 2014
The twins and their parents got off the elevator in the lobby of the beach-front hotel. The kids were in bathing suits, their parents were dressed in comfortable shirts and shorts.
“You have your keycard?” their mother said to Mabel. She grinned and waggled her shoulder bag that also contained her towel and suntan lotion. She bumped it playfully into Dipper’s matching bag. “Good. Your father and I are going to check out the casino further down the strip. You two go enjoy yourselves in the pool and on the beach, but make sure you both leave time to go back up to your room and change before dinner.”
The Pines family didn’t often splurge, but it had been a busy and successful year for both of the twins’ parents. They decided the family could enjoy a trip south to a Caribbean island resort for March break. It was a great surprise for their children, who had never in their fourteen years been on a tropical vacation.
Dipper and Mabel immediately headed outside to the hotel’s pool. The heat of the sun and the cool of the water combined for a comfortable and pleasant early afternoon as they played on the waterslides and splashed each other in the deep end.
It was a great opportunity for Dipper to admire Mabel’s body. The one-piece suit she wore wasn’t tremendously revealing, but it did nothing to hide her developing curves. Dipper dove underwater often to get a clear, unobstructed view, and really wanted to be able to slide his hands along her small but feminine breasts, hips, and behind. Thankfully, the temperature of the water was low enough that his penis didn’t advertise his admiration too noticeably.
But soon enough, they agreed that they had experienced as much fun as could be had in the pool. “To the beach!” Mabel screeched, sending one last splash of water at her brother before swimming quickly for the ladder. Dipper followed, happily taking in the view of her backside as she pulled herself out.
As they walked to the ocean across the beautiful sand beach, Mabel continued her own subtle appraisal of Dipper’s maturing physique. He was still skinny, but muscle definition was also becoming noticeable in his arms, shoulders, and mostly-hairless chest. She wished his swim shorts weren’t so baggy, so that she could see if his ass was as cute as the rest of him.
They decided they wanted to see how the water was, but they had to set down their bags. Looking around, Dipper didn't see anywhere they could safely leave them unattended.
He saw a large group of at least three families with children, heading further up the beach and carrying similar bags as the twins were. In that direction, the shoreline curved out into the ocean and the sand piled up into a dune, so that the section of beach beyond was hidden from the busy area directly in front of the hotel. Ahead of the group, other beach goers were cresting the dune and disappearing from view as they descended to the other side.
“Let's see where they're going,” Dipper suggested. “There might be places to stash our bags there.”
Over the next few minutes as they strolled down the beach, the twins continued their unconscious flirting with each other, the surrounding waterfront much less important than spending time focused on each other. As they began climbing the shallow slope of the dune, they failed to pay any attention to a sign that was posted beside the path.
Mabel had just finished putting forward a funny theory on how Mermando’s family might be from around the island, when they reached the top of the small hill.
“Uh ... Mabel?” Dipper said slowly. Mabel saw that he was staring at the beach before them, and she also looked.
This section of the beach was less crowded, but there were still more than enough people for the twins to see that this was a “clothing optional” beach.
At first, both of them were hit by the urge to immediately turn around and go back: they were uncomfortable because they had never seen casual nudity before. But then they noticed that none of the people were acting strange about it. There were sunbathers and swimmers of all ages, from toddlers to seniors, all enjoying not being encumbered by swimsuits. They noticed that there were several teenagers that looked about their age, as well. No one was showing any shame, regardless of how fit, or how out of shape, they were.
Mabel looked back at Dipper carefully. “You … wanna stay here?” she asked, not sure of what she wanted to hear as a response.
Swallowing, Dipper was about to take the safe way out and turn around. Then he locked eyes with his sister, seeing that she was trusting him to decide for them.
He hoped he knew what he was doing. With a shy grin, he replied, “Sure … why not?” Mabel’s face broke into a smile that surprised both of them.
They found themselves a spot on the beach that was not too near any other people and spread their towels beside each other. For several moments, they just sat there, glancing around at each other and at the sunbathers, but not really looking. There were naked people in every direction, casually displaying body parts that the kids had never seen in real life before.
“Dip, we’re … uh … kinda the only non-nudified people here,” Mabel said quietly.
Dipper took a deep breath. “Then … let’s just do this?” he said, pulling the drawstring to his swim shorts and pushing his thumbs under the waistband.
Mabel pulled the straps of her suit down off her shoulders, holding the garment to her chest with her hands. Then she nodded. “Let’s do this!” she replied bravely.
The twins lifted their butts, pulled down their suits to their ankles and removed them, dropping the pieces of fabric beside them. Hugging their knees in front of them, they were naked in front of each other for the first time since they were probably two or three years old. After a quick awkward moment of half glances at each other’s bodies, they managed to lay down side by side on their stomachs, resting their heads on their arms and staring wide-eyed directly at each other.
“This … is … cray cray!” Mabel whispered loudly.
“Yeah!” Dipper said in a hushed voice. “... Are you all right?”
Dipper’s protective concern immediately relaxed Mabel. “Yeah, I’m good, I think.” She took a deep breath, a large smile of relief spreading on her face. “It feels … really amazing to be naked out in the open!” she said as she gleefully squirmed on her towel.
“Yeah … it does!” Dipper said, starting to grin as well. He surprised himself with the truth of the statement. Dipper had always been the more self-conscious of the pair, and he could only assume it was Mabel’s presence that was driving him to so adventurous. To be naked! In public! He liked the feel of the light wind and the sun, both now caressing his entire body. It was a very freeing experience.
For the first few minutes the twins just talked, slowly getting accustomed to being naked. People strolled to and fro past them, some heading to the ocean, others just enjoying a walk.
Mabel had seen enough. Actually, she hadn't seen enough, at least not enough of Dipper. And taking the opportunity to let him see all of her? She wanted to do it now. It was time to get off the towels.
“C’mon, Captain Cheese Dip,” she invited, lifting herself off her elbows and up to her knees. Dipper had a perfect up-close view of the front of her body, and he gulped involuntarily. She reached to grasp his hand. “Let's go try swimming now!” She got to her feet, relieved that her brother didn't resist as she pulled him upright, as well.
Before taking a step to the water, they took a moment to appraise each other's bodies, but trying not to look too interested. Mabel thought Dipper’s “dipstick” was fascinating: he had a sparse patch of hair surrounding the base of a penis that wasn’t fully hard, but definitely wasn’t tiny, either. She couldn’t help but admire it, and how cute it was when it and the sack behind it swayed slightly with Dipper’s movements. Meanwhile, Dipper was trying and largely failing to not to stare at his sister. The tiny bounces of her breasts were wonderful, as were her perfect-looking nipples. What he could see of her crotch was mostly just a light fluff of hair with a puffy slit beneath it. She was as beautiful as he had imagined.
They didn’t even notice they hadn’t released each other’s hands. Dipper was blushing as he rubbed the back of his neck. “You … look nice, Mabel,” he mumbled bashfully.
Mabel’s blush radiated across her skin, as well. “Aw, thanks Bro. I … think you’re lookin’ pretty fine, yourself.” Their gazes met again, and each saw the same embarrassed grin that graced their own face. Mabel snorted, causing Dipper to bark a small laugh, and the ice was broken.
For the rest of the afternoon, the twins hung out, with the same odd vibe of seemingly oblivious attraction. Only now, they were nude, which ratcheted up their emotions that much higher. Every touch, every glance was more electric. As they swam and played in the ocean, hands and feet would “accidentally” glance across each other's skin. Back on the beach, they helped each other apply sunscreen where bathing suits had previously covered. Mabel confirmed that Dipper’s butt was, in fact, very cute, and she shivered as she applied the lotion for him. Everything was wonderfully exciting, quietly frustrating, and very arousing.
Dipper in particular had difficulty with the obvious physical evidence of his excitement, particularly as his earliest fantasies of him and Mabel together took place on the beach of the “Blue Lagoon.” His penis was in a “mostly erect” state all afternoon, his brain and body at war constantly over what condition he wanted to present himself to Mabel. He made several clumsy, stuttering attempts to blame his “condition” on the wind or just anatomical fickleness. Although she was mightily tempted, Mabel sensed she shouldn’t make fun of him, and gradually Dipper became more comfortable with himself being completely exposed.
As dinner hour neared, the teens reluctantly put their bathing suits back on for the walk back to the hotel. They both now agreed that the whole concept of having to wear them sucked, but such was life.
“Well I'm glad we did that!” Mabel said, wrapping her arm behind Dipper's slightly sunburned back and shoulder as they neared the hotel. “Another exciting chapter in the New Adventures of the Mystery Twins!”
“Mabel!” Dipper groaned, cringing at the thought of anyone, particularly their parents, learning that they enjoyed a nude beach together.
She laughed and poked him playfully. “And you know what? This is all practical, too!” Mabel continued. “Now for the rest of our vacation, we don’t have to run into the bathroom to change our clothes. I mean, what’s the point, after today?”
Dipper didn’t want to disagree with that logic, but he had an immediate need to have the bathroom all to himself: he desperately needed to relieve the uncomfortable pressure that had built in his testicles all afternoon. There was no way to explain his urgency, not without revealing that he had been so turned on by her all day, he’d literally been in pain. How would that sound? No, he couldn’t explain it to her at all.
Once in their room, he hastily grabbed his clothes and headed straight for the bathroom. He brought himself to orgasm after only a few seconds of rapid stimulation, washing away his first case of “blue balls” in a wonderful wave of satisfied bliss.
However, that relief came at a price. Mabel thought he had changed his mind about how cool it was to be so open with each other. Not wanting to push things, and feeling like she should avoid embarrassing him further, she waited until Dipper emerged from the bathroom, then she also used the privacy of the locked room to change her own clothes.
He noticed her awkward change of attitude, and knew he was the cause, but felt helpless to do anything about it. The end result was that the twins buried whatever progress they had made that day in developing their relationship. For the remainder of the vacation, they kept their distance in their hotel room, and never suggested to the other to sneak off to the nude beach again, even though privately they both wanted to.
Spring 2014
Going to the prom was a stressful enough event for any student at Piedmont High. For some, it was not pleasant at all.
In general, Grade 9 freshmen were largely unattached, often still forbidden by parents from going on dates until they were older. But that didn’t stop a lot of young students from going anyways. Groups of boys and girls would gather together, occasionally asking or being asked to dance by someone from another group.
Mabel was similarly restricted from dating. She had no date to the prom, but she decided to go anyways and be with “her people”, as she referred to her small posse of oddball friends.
It seemed like she was having a good time. Because she was outgoing and was always hamming things up in classes, she enjoyed a kind of popularity at school. She certainly wasn’t one of the cool girls: instead, her upbeat attitude and always-friendly demeanor made her approachable to “normal” boys. She didn’t lack for dance partners as the night went on.
But Mabel was growing more and more upset with every moment of the prom. All around her were couples, happily enjoying the evening together. There were kids developing new feelings. And from some of the boys she danced with, she saw signs of genuine affection. Some of them kind of liked her.
And Mabel was having none of these emotions herself. Not for anyone at the prom, anyways.
Dipper had stayed home, saying he wasn’t interested. Mabel had half-heartedly tried to get him to go, but secretly she was glad he didn’t. She didn’t know what she would do if she saw some other girl approach her brother and ask him to dance, or even worse, if he'd asked some other girl himself. And she’d have had to resist asking him to dance herself, because at prom, that would be very strange. But now Mabel missed Dipper. And it hurt her to realize that the boy she wanted to do all these “prom”-y things with was the boy that she couldn’t ever have that happen with. She got more and more down in the dumps as the evening went on.
Their mother had volunteered to pick up Mabel and her friends from the school, dropping them all off and finally arriving home after one in the morning.
“But you had fun, didn’t you?” the twins’ mother said as she unlocked the door and entered their home.
Mabel shrugged. “There was lots of romancin’ goin’ on, but none for me!” she griped.
Her mother tsked and squeezed her shoulder. “Oh, Pumpkin! We think you’re too young to have a boyfriend yet,” she said as they climbed the stairs to the second floor. “You’ll be ready to start dating boys in the next little while, I think. In the meantime, you shouldn’t stress about it.” She nodded to the light peeking out from beneath her brother’s bedroom door. “Dipper stayed home. He had the right idea. Looks like he’s still up. Say goodnight to him before you turn in, okay?” Her mother kissed her cheek and went into the master bedroom, closing the door behind her.
Mabel paused before she could tap on Dipper’s door. Did she want to see him at that moment? Wouldn’t that just be the final stake through her chest? To see everyone else able to act on matters of the heart wasn’t enough? Dipper being her brother reinforced why she couldn’t act. She’d fallen in love with someone who she could never have. To face him now was too much! She turned around, ready to just collapse onto her bed.
Dipper’s door opened as she crossed the threshold to her room. “Hey,” he said quietly. “I thought I heard you co- ….” His voice trailed off as Mabel went into her room without turning around, and starting closing her door. Dipper leapt forward and held it with his hand. “Mabel, what’s wrong?” he asked, concern evident in his tone.
“Nothing, Dip,” she grumbled. Still, she allowed Dipper to follow her in.
He carefully closed the door behind him. “Mabel, it’s not nothing,” he said. “You didn’t have a good time at the prom?”
Mabel sat on her bed and flopped unceremoniously onto her back. The frilly spaghetti-strap prom dress splayed out, much as her arms did, as she stared at the ceiling. “Using those mad investigation skills to figure that out ... Inspector … Dip-adget?”
A tiny smile crossed Dipper’s mouth. “That was the worst play on words I’ve ever heard from you.” Then his face turned sympathetic as he sat down beside Mabel on her bed. “Now I know you didn’t have much of an evening. C’mon Mabes!” He reached over half-heartedly to tickle her kneecaps. “Out with it.”
Mabel was in too fragile a state to play her usual “affection game” with Dipper: she was afraid her true feelings would spill out, She batted away his fingers, then covered her face with her hands. “I can’t, Dipperrrrrrrr,” she groaned.
She heard Dipper’s voice harden. “Did something happen at the dance?” he asked. “Did someone do something to you? I’ll-”
“No, Dip,” she interrupted, “nothing happened.” His protectiveness, the way he cared about her, made her love him more than ever. Why did he have to be her brother? Why couldn’t he be someone who could feel the same way for her that she felt for him? “I’m just … it’s me! I’m too … weird for all this romance-y … prom-y ... poop!” she mumbled through her palms on her face.
“Yeah,” Dipper replied solemnly. “I know how that feels.”
The tone of his voice poked a hole in Mabel’s shield of self pity. She dropped her arms and looked up to Dipper, who was just staring at his ankles as he sat beside her. He looked just as down as she felt. She kicked herself for not seeing it, for giving in to her old selfish tendencies. Regardless of her own down-in-the-dumpiness, and that he was the reason for her mood, it wasn’t his fault. Her broski looked like he needed some old-fashioned TLC, and darnit, she would buck up and give it to him!
Mabel sat back up and turned towards Dipper. “C’mere,” she said as she wrapped her arms around him. “Dippin Dots needs hugs!” She pulled him close and nuzzled her head into his neck, inwardly knowing she wanted this just as much as she thought Dipper needed it.
She sighed happily when Dipper didn’t hesitate at all. He immediately returned the hug and rested his cheek against Mabel’s ear.
There was a long moment that neither twin moved. Mabel wasn’t even sure how much time had passed. She only knew that she was more at peace than she had been for a long while. Without thinking, she twisted her position to get more comfortable, pressing her breasts into Dipper’s chest as she reapplied her squeeze.
For a split second, Mabel feared Dipper would freak out at this. But instead, he also shifted to accommodate, burrowing his face into her hair. They were sharing the most snug, intimate embrace she had ever experienced.
Everything Mabel had been feeling for two years, all the pressure she felt on her heart from the prom, overflowed in that moment. She couldn’t stop it, and she didn’t want to stop it. She had to let out what she desperately wanted to say.
“I love you Dip,” she whispered.
She felt his muscles tense, and instantly Mabel feared the worst. He was creeped out! He was disgusted! For what seemed like forever, they were frozen in the hug. She opened her mouth to explain away the words, to say that she didn’t mean it that way, when she heard Dipper’s tentative whisper in reply, “I … love you too!”
Mabel felt Dipper take an uneven intake of breath. Slowly she pulled her head back so she could see his face. The instant she saw the look of fearful longing, the quivering lower lip, the wide, moist eyes … the moment he released a shuddering sigh ... all doubt was gone. Though their mouths were only an inch apart, Mabel wanted to dive forward, lest the moment slip away.
And she was delighted when Dipper beat her to the punch. He leaned in and kissed his sister for the first time, a kiss that she returned passionately.
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Unexpected (a Pinecest story)