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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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- 5
Summer 2014
“So … here we are!” Dipper said nervously after closing the attic door.
Mabel stood close to Dipper. She twisted her hair in her fingers, a habit that gave away that she was a bit anxious. “Yup! … Right here!”
Dipper took a step forward, his right hand vigorously scratching the back of his neck. “Are y- … are we sure we wanna do this?”
Touched by her brother's concern, Mabel felt her worry melt away. She took a deep, confident breath. “Yeah, Dip. I am!” She reached behind his head and held his hip in her other hand. One look into her brother’s adoring eyes, and all doubt was gone. She wanted this!
Mabel smiled, attempting a seductive tone. “I … hope you are, too.”
His sister’s self-assurance was exactly what Dipper needed to hear. “Yeah!” he whispered dreamily in reply, leaning his head down carefully from his slight height advantage to kiss her.
A week had passed since their first kiss. In that time, the twins had kissed many more times, and had explored and confessed their feelings to each other.
The night of the prom, they were still uncertain. They had kissed enthusiastically, but then as they clumsily laid down on Mabel's bed, the spaghetti straps on her dress snapped, exposing her breasts as the top of the dress fell down. They both awkwardly agreed that it would be best if Dipper were to return to his room, even though they had seen each other naked just a few months before. Later they would talk about how they both felt, that everything could have spiralled out of control. And with their parents just down the hall, they were likely correct shutting things down on that first, incredible night of discovery.
In the days that followed, both of them were still insecure, wondering if their twin would start feeling sick about what they were doing. Neither could be sure that their dream wouldn’t still revert into a nightmare.
They could scarcely believe it, but they came to realize the dream was true! Slowly they revealed to each other how they had felt for so long. Tears flowed as they quietly stole away brief moments together, making a connection they had denied themselves even the hope of ever happening.
However, such moments were brief, and very scarce. Final exams needed to be written the whole week following the prom, so they needed to study. Their parents were around, of course. And they had to get packed, as they were scheduled for a third summer in Gravity Falls, and they would leave the weekend immediately after exams. They barely got to second base together, and the whole time they were afraid of getting caught, and terrified to ask the other just how far they wanted to go with this new relationship.
It was on the long bus ride north that the twins finally had time to talk. They were both elated, and somewhat scared, to admit to one another that they both very much wanted to do more together. Much more. As in “all the way” more!
But if that was actually going to happen, they agreed they needed protection. They could not act foolish. At a rest stop on the bus ride, a red-faced Dipper tried to sneak nonchalantly into the washroom, where he purchased two condoms from the vending machine. He was certain that every person present in the restaurant was staring at him and judging him for what he planned to do with his sister.
Now the two of them were alone in the attic of the Mystery Shack late that same night. They knew that they wouldn’t be disturbed, since Soos said he was busy fixing a display case and Melody was occupied feeding their infant son.
Dipper had to break their kiss to pull the condoms from his pocket and drop them on the night table between their single beds. Then they quickly fumbled with buttons and zippers, all the while kissing all over their sibling’s face and neck. The pent-up desires of the past week drove them to dispose of their clothes as rapidly as possible. As they stood naked and close to one another, they looked each other up and down unabashedly.
“You're so beautiful,” Dipper whispered, tentatively running his hand through Mabel’s long hair and across her shoulder, while his eyes bounced up and down between her face and her breasts.
Mabel’s breath caught as she lightly dragged the fingers of both hands down Dipper’s chest, then across his flat stomach to his waist. She gripped his skin and drew herself a half-step closer, leaving only a few inches between them. “You’re pretty handsome yourself!” she breathed in reply.
Their lips touched again, and their bare bodies came together. Mabel’s naked breasts pressed tantalizingly against the skin of her brother’s chest. Fingertips and palms first caressed shoulders, waists, and backs, then moved to hips, breasts, and butts. Dipper’s very erect penis poked between Mabel’s legs, the top of his shaft nestling its way into her folds as the twins panted unsteadily into and around each other’s mouths. Their pelvises began grinding together, seemingly of their own accord.
One of Dipper’s hands moved around from Mabel’s behind to slide between their bodies. Palm facing his sister, he reached down to explore between her legs. His middle finger found the top of her slit and he moved it down an inch, right into the wondrous hot and wet channel, and over a small bump. Mabel gasped and her eyes squeezed shut, her body clenching at Dipper. He wasn’t sure if this was a pleasant or painful reaction. “Are you okay?” he verified, supporting his sister’s body with his free hand while holding his finger immobile.
“Yeah!” Mabel breathed in reply with a nod. Dipper decided to try that bump again, and he slowly drew his finger up and back down, completely overwhelming her. “Oooooo yeeeeeaaaaaaah!!” she moaned, one hand clutching tighter behind his neck while the other reached to grasp Dipper’s penis for the first time. She had just enough brain power to command her hand to pull on it up and down next to her vagina as she rode through the wonderful stimulation on her clitoris.
Dipper tensed and groaned as well. “Oh god!” he gasped in pleasure, setting his finger to work on that magical button he’d found.
The twins fingered and stroked each other to ever-increasing levels of arousal, pressing their mouths together to stifle the passionate noises they were making. It didn’t take long before Dipper’s whimpers grew louder and higher pitched as Mabel’s pants and gasps became deeper and throatier. Finally, Dipper winced hard, an almost pained expression on his face, and Mabel felt his penis throbbing as warm semen splashed on her thighs. An enormous orgasm of her own took hold, Dipper doing his best to hold her as they both rode out their intense first sexual moment together.
Basking in the afterglow, they moaned quietly and gently continued kissing as they came down from their fervent high. When their lips finally parted, Mabel’s eyes fluttered open to find Dipper staring dreamily at her in loving amazement.
“Wow!” he said in a low voice, a small smile spreading on his blissful face.
Mabel thought he looked adorable. She pushed herself up onto her toes and kissed Dipper’s nose. “Boop! Ya mushy nerd!” She giggled, releasing her grip from his rapidly-softening penis, then pulled back a bit to survey her legs and fingers. “Eww! You’re a messy nerd!” she exclaimed with a grin.
Dipper blushed despite their intimate position together. They didn’t have a towel nearby, so he grabbed his t-shirt off the floor and shyly helped Mabel wipe up.
“Well! Now that that’s out of the way …” Mabel declared, she pounced on her brother, knocking them both back onto his bed. “I declare Cuddlin’ Time!” she murmured into Dipper’s ear as she rolled off him and onto her side. Dipper turned to face her, and their arms and legs naturally wrapped around each other. They squeezed each other tight, then relaxed with satisfied sighs, still in each other’s embrace.
For several minutes, the twins lay together side by side, comfortably on top of the covers in the warm night air, noses almost touching, slowly caressing one another’s skin as they whispered how much they loved each other, and how long they’d been waiting to be with one another. Dipper chuckled as he recounted how he had overheard Mabel getting herself off in that very room the previous summer on their first night returning to the Shack.
“Oh yeah? Well F-Y-I, Bro Bro, I seem to recall some serious personal time activity goin’ on in this bed the very next night!” Dipper reddened again, immediately aware of the event in question. “You remember what you were thinking about that time?” she teased in an exaggerated sultry tone.
“Every moment,” he replied, immediately serious. His palm brushed hair from her face, and his hips made a small, unconscious thrust. “The two of us were stranded on a desert island. We were alone, just us … we were on the beach-”
“Was the sun shining?” Mabel asked, grinning and clamping her eyes closed.
Dipper closed his eyes as well as he remembered his fantasy of the Blue Lagoon. “Yeah. Warm, but not too hot. A nice cool breeze, too.”
“Hmmmm!” Mabel hummed happily, squirming closer, rubbing herself onto Dipper’s body. “The sounds of waves crashing, lots of birds crying, too!”
“That smell of sea salt coming from the ocean,” chimed in Dipper with a smile, getting into the imagery in his head, his hand sliding down Mabel’s ribs towards her hip.
Mabel giggled as she rolled her pelvis into him. “That crazy feeling of your brother’s thing poking against you!” Dipper bashfully opened his eyes to find Mabel already giving him a saucy stare. “We were lying on our sides? Like we are now?”
Dipper shook his head slightly. “I was lying back ... you were … on top of me.”
“Oh. Like this?” Mabel murmured as she pushed herself off the mattress and carefully slid herself over Dipper, pushing him over onto his back. She straddled him at his thighs, his fully recovered erection pointing up at her chest, then she leaned forward and wriggled up his body. Dipper’s penis was now trapped against his stomach, and he gasped as his testicles and the underside of the shaft rubbed along Mabel’s vagina as she moved up his body. She ground against his length repeatedly as she leaned down to Dipper’s aroused face. “Is this more like it?” she asked teasingly.
“Uh huh!” Dipper managed to reply, his hands gripping lightly on Mabel’s smoothly gyrating hips. “You’ve … almost got everything right!”
Starting to breathe harder again, Mabel smiled, eyeing the condoms on the night table. “Almost, huh?” she panted and she continued moving. “What am I not doing right … I want it to be as … perfect a recreation as possible!”
Dipper swallowed, a hand moving quickly up to Mabel’s cheek. His face turned pleading. “Mabel … “ he whispered. “Please … just let me know this is … this is what you really want!”
Mabel felt spontaneous tears spring into her eyes. She slid her own hand up to her cheek and gripped his hand. “Yes, Dipper,” she replied sincerely, no hint of joking in her voice. “I love you! I’ve wanted this for a long, long time!”
“I love you so much!” Dipper breathed. Then he reached over and snatched one of the condoms. Mabel watched in amusement, continuing to grind on Dipper’s groin, as his shaking hands struggled to tear open the foil wrapper. After he managed to extract it, he looked at it obtusely, trying to concentrate through the distraction Mabel was giving him lower down. “I’ve … never used one before …I’m not sure …”
“I’ll help!” Mabel chirped excitedly, taking the disc and sliding back down Dipper’s body. He watched, nervous and excited, as Mabel held his penis steady and placed the condom on the tip. Dipper felt her warm breath on his member as she moved her face close. They both watched, fascinated, as she rolled the condom down his length.
There was a small problem: the condom was obviously too large. They looked doubtfully at the latex sheath draped loosely over Dipper’s fourteen-year-old penis. “Oh well!” Mabel declared, her smile covering up any concern that might show on her face. She scrambled back up, holding Dipper’s covered erection to her virginity with one hand and his shoulder with the other.
She lowered herself down until she felt Dipper’s tip notch into the entrance of her vagina. Then she let go of the shaft and leaned forward so she and Dipper could watch each other’s faces. “Here we go …” she whispered, hiding her nervousness as she began to bear down.
As she pushed down, nothing happened at first. She felt Dipper pushing up at the same time, increasing the pressure. Mabel bit her lower lip. Then some of the friction was suddenly overcome, and over an inch of Dipper’s length penetrated at once. Mabel couldn’t mask her discomfort as she was stretched painfully.
Immediately relaxing his pelvis, Dipper’s hand went to her face. “I’m hurting you!” he said, alarmed.
Quickly wiping her eyes, Mabel said, “No, I’m okay! I’m fine! Let’s keep going!”
Being a virgin, Mabel didn’t know she really wasn’t prepared to have sex. She was tight and a bit nervous, neither of which make any girl’s first time easy. Between herself and the rubber, there was too much friction for their coupling to go smoothly. And Dipper wasn’t free of discomfort himself. Being unfamiliar with condoms, the twins had no idea that he was supposed to pull back his foreskin prior to rolling on the rubber. The loose sheath was now folding up at the tip and pulling the foreskin down over the head as he entered Mabel. The delicate, normally protected skin of the head began rubbing tightly against folds of latex without any lubrication.
Mabel was determined that she would show Dipper the full amount she loved him, even if this hurt her a bit. Impulsively deciding that the “ripping off the band-aid” method was the best way to go, she took a deep breath and dropped down with all her weight.
Both twins cried out in pain. Tears ran, uninhibited this time, down Mabel’s cheeks. Dipper clenched his teeth to keep from shouting as the bunched up condom dragged across the exposed tip. She gingerly lifted herself back off, the condom coming loose and yanking off of Dipper’s penis, stretching and rubbing at the sensitive head again as it came away. This caused another exclamation of agony that Dipper muffled with his own hand. Mabel was sitting beside him now, doubled over trying to deal with the awful experience of a deep, unlubricated first-time penetration.
Soos’ voice called up from the bottom of the stairs. “Hey dudes! You all right?”
Dipper took a deep breath. “Yeah Soos!” he yelled. “I just … stubbed my toe! I’ll be fine!”
“What about Hambone?” Soos continued. “I swore I heard Mabel scream, too?”
“It’s okay!” she shouted shakily. “I … I stubbed my toe, too!” Dipper gave Mabel and incredulous look. Mabel shrugged back helplessly.
“Woah, random number theory! What’re the odds?” Soos called back. “Ya want ice packs, or anythin?”
“We’re good!” they yelled back together.
The twins spent the next few minutes recovering, getting over the panic, pain, and embarrassment. At first they had trouble looking at one another, now uncomfortably naked, not feeling at all sexy. Dipper turned his head away while Mabel held her shins in an invisible Sweater Town position.
Mabel shifted, inhaling uncomfortably as the nerve endings in her crotch protested. Finally, she broke the silence. “Guess that coulda gone better, huh?”
Dipper snorted derisively. “Yeah, you think?” He rolled over away from Mabel to hide his face and his sore and completely flaccid penis. “I’m sorry,” he said softly after a short silence.
“I'm sorry too,” Mabel mumbled. Then a moment later, she smirked and put her palm on Dipper's hip. “And sorry to Mr Dipstick, there!” she chuckled softly as she slid her hand down to try to tickle his genitals.
Still upset, Dipper squirmed and pushed Mabel's hand away. “Mabel, I hurt you! How can … how can you even want to touch me again?” he said bitterly. “I wish that … I’m just sorry we did all this at all!”
“Hey!” Mabel replied, caressing his arms and back. “I'm not sorry about that! I mean ... yeah, that really didn't live up to the harlequin romance level first-time experience there, but we experienced it. Together! I would never have been able to handle having anything like that happen with anyone else!” Dipper still faced away, but he was no longer trying to avoid her touches. “The Mystery Twins will figure this out! And then next time, it'll be way better!”
Dipper rolled back towards Mabel, tearful astonishment clearly evident on his face. “Next time?” he asked weakly. “You … still want there to be a next time?”
“Well, not tonight, for sure!” she said, laying her head on her brother’s chest and hugging his torso. “But you're not goin’ anywhere, and neither am I! You can bet your super-adorables little butt there's gonna be a next time!”
A relieved and thankful Dipper finally returned the embrace, placing a long kiss to the top of Mabel's head. She made happy, satisfied noises in return.
“I love you so much,” they said in unison, causing them both to smile even wider.
There was indeed a next time. Many more next times, in fact.
The following day, their first full day since arriving in Gravity Falls, Soos gave the twins the whole day off to rest from their long travel day. Mabel got to help Melody take care of little Stan Jr, while Dipper and Soos drove to town to pick up supplies. Afterward, they were given the full tour of the extensive renovation Soos had given to the Shack. Business had been so good, all the available space in the building was needed for new displays and attractions. Soos had built a large addition onto the back of the building, providing new living space for his growing family and himself, plus an apartment Grunkles used when they were home between adventures.
The only space in the older part of the structure that Soos could not adapt for tourists’ use was the attic, so it was left to be the domain of the twins for whenever they felt like coming up from the city. And for the remainder of the summer, the isolated attic provided a perfect, very private place at night for Dipper and Mabel to physically explore their new romantic relationship.
That night, Dipper showed Mabel the lubricant and “snugger fit” condoms he’d managed to buy in town when Soos wasn’t looking. They fooled around, giggling as they practised putting the rubber on the correct way, getting more comfortable and relaxed. The following nights they experimented with more touching and fingering, then with oral sex.
By the weekend, they felt they were ready to try intercourse again. This time all their preparation and practice paid off, and they both had a very pleasurable, loving experience.
For the remainder of the summer, Dipper and Mabel couldn't imagine their lives could be better. They had fun and interesting jobs, money in their pockets, no commute time to or from work, the best landlord and boss in the world, occasional visits by their favorite great uncles, and most importantly, the freedom to love each other almost without restriction. Dipper had to return to town often as the weeks went by: his visits to the pharmacy for “supplies” actually increased in frequency as time went on.
As August came to a close, their return trip to Piedmont loomed. Their last night in Gravity Falls was bittersweet, as they made love tenderly, but despairing that their hedonistic summer was done. They would be home for their fifteenth birthday on Sunday, then school the next week, but none of that seemed important at all. They snuggled and fell asleep together on Mabel’s small bed, as they had done most nights this summer, for the last time.
The bus ride home provided the twins hours of uninterrupted time. There were few other travellers on the coach with them.
Mabel was chattering happily about seeing Waddles and Mittens again, reacquainting with friends, and even about starting school once more. She talked rapidly, nearly nonstop. Meanwhile, Dipper brooded and said little, holding Mabel’s hand and lightly running circles over and over into her palm with his thumb.
Then their eyes met, and in an instant they both knew they couldn’t avoid it any longer.
“Mabel …” Dipper asked softly, “... what’s going to happen to us?”
She squeezed his hand back, still smiling. “Hey, Chip Dip, don’t worry! We’ll make this work, we … just have to be a lot more careful, making sure Mom and Dad aren’t around, I guess …”
Dipper shook his head. “No Mabel, not that … I mean, yeah we need to talk about that too … but …”
Mabel saw the worry on her brother’s face. “But what?”
He averted his eyes. “Let's say we're careful. And lucky. Mom and Dad don't notice. We manage to hide this from everyone at school.” He paused, then continued. “How long will it be before we make a mistake? How long until our luck runs out?”
“I …”Mabel started, but found she didn't have an answer.
Continuing to stare at the back of the seat in front of him, Dipper went on. “Maybe we somehow get through high school. What then? Do we go to college together? Can we keep hiding this from everyone if we do that?”
Mabel knew now that this had been bothering Dipper for some time. She waited with trepidation for him to finish.
“So we go to college. We get our degrees. Then what? … How do we hide then? … We can’t ever get married, we can’t ever be normal, we can’t ever have-” Dipper’s voice cut off.
She looped her arm around his back and pulled him to her. “Dipper, whatever games of hidin’ and seekin’ we need to do, we can do it! We’re still the Mystery Twins, figuring weird junk out!”
“Or …” Dipper’s voice hitched. “... or what if … one of us doesn’t want to keep hiding? That keeping this secret just gets to be so much … y- one of us starts thinking it’s not worth it ...”
Mabel heard the slip in Dipper’s explanation. He was afraid she would break up with him when it became too difficult to continue masking the truth of being in a secret and forbidden relationship. That he thought she would dump him when the going got tough.
“Dipper Pines, look at me!” she interrupted.
Reluctantly, Dipper turned his head towards his sister. He knew he was in trouble, that she had heard that he thought she would be the one to break things off someday.
But instead of anger or hurt, he saw nothing but affection and sincerity on her face.
“I love you, Dipper. I’ve known that for two years, but now I can say that, in a way, I’ll have loved you fifteen years tomorrow! You are more to me than anyone else ever could be!” She placed her hands on his cheeks. “We were born a pair, and we’ve always had each other. I know that I never, ever want to you lose you!” She felt tears running between her fingers. “I want to be with you, no matter what! Maybe we have to be sneaky, maybe we tell Mom and Dad someday, maybe we let the whole world know they can kiss our cute matching asses … I can’t imagine what my life would be like without you, Dipper, and I never want to find out! Get that into your big ol’ brain! Okay?” she cried quietly, her cheeks now as moist as her brother’s.
Dipper sobbed loudly while reaching out to grab Mabel, desperately pulling her to him. They cried openly as they hugged and kissed with fervent need, uncaring if anyone around them was watching. They might not have all the answers of what lay before them, but both of them now knew that they were committed to face the challenges ahead together. They were in love, and that was all that really mattered.
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Unexpected (a Pinecest story)