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Fistbump 2: Unspeakable (a Pinecest story)	By : Edward_or_Ford Category: +G through L > Gravity Falls Views: 21283 -:- 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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Tuesday came, and with it came Dipper and Mabel’s first day at Piedmont High School. They were due to start Grade 9.
Mabel was looking forward to seeing her old friends from middle school again, and hopefully making new friends. They had so much to catch up on, as she had not seen anybody since leaving for Gravity Falls after their last class in the spring.
She also hoped that seeing friends again would help take her mind off her new life at home. Boy, is it difficult to practise method acting all the time! she thought. Every moment that her parents could see her, she was “on”: the hammy, carefree Mabel that they had known and loved for fourteen years. She found that she was even denying herself the ability to turn it off when she was alone, it was too hard to switch back when necessary. Maybe away from Mama and Daddy, I can get a bit of a rest.
Dipper was looking forward to classes beginning again, but not to having to enter on the lowest rung of the social ladder. He was still a bit short for his age, and thought he was scrawny even for his height. Plus he was pretty much a huge nerd. He knew that high school was where everyone got sorted into cliques, and he hoped that the jock set at this school would go easy on the geeks.
In the high school jungle, having a girlfriend can be a great defense against the alpha gorillas. Just his luck, he had the best girl he could ever hope for, and couldn’t even show her off at school, and would never be able to.
The high school was right beside the middle school, still walking distance from the Pines family home, so the twins walked together, carrying their backpacks. As they walked down the upscale neighborhood streets toward school, they had their first opportunity to privately talk since their arrival off the bus, days before.
“I love you, Dipper,” Mabel said quietly.
Dipper looked around for anyone in earshot. “I love you, too,” he replied quickly while looking down, then added, “I miss you,” glancing up at her face.
“Ditto,” she said with a small smile. They walked without speaking a bit further.
Dipper looked over, concerned about Mabel’s uncharacteristic silence. She had seemed to be handling things so well the last couple of days, appearing so normal (well, “normal” for Mabel, anyway) around everyone, but now he wasn’t so sure. “You okay?” he asked sincerely.
“I guess,” Mabel sighed. “I just have to get used to this. It’s hard being ‘Mabel’ all the time! Now’s the first chance I’ve had to be me since we got home.”
That’s a weird thing to say, Dipper thought. “What are you talking about?” he asked with a smile. “You are Mabel!”
“I’m talking about the character I’m playing at home. You know, ‘Mabel!’” she emphasized with air quotes. “The silly goofball who’s not in love with her brother?”
Dipper considered that without speaking for few steps. Finally, he said quietly, “I hope ‘Mabel’ isn’t just a character anymore.” He paused again, looking at her shyly. “I happen to love the silly goofball!”
Mabel felt herself blush at his sappy comment, and immediately decided she needed to return the favor. “Yeah, but does she do this for you?” she asked with quiet innuendo, as she crossed over in front of him to walk on the other side of her brother, quickly grabbing his crotch along the way. Dipper jumped in surprise and alarm.
“Mabel!” he scolded her hoarsely, then looked up and down the street. “You can’t do that! It’s too risky! What if somebody sees?”
She pouted for a second, then grudgingly agreed. “Sorry. Couldn’t resist. I won’t do it again.” She looked over to him again shrewdly. “Not until tomorrow night, that is!” she purred.
A happy tingle ran up Dipper’s spine on hearing Mabel’s promise to him. On first learning of their parents’ plans to attend a Bible study on Wednesday evenings, he wondered if it was really the best idea to sneak in “quality time” together so quickly after they agreed they needed to stay apart. Mabel was obviously in favor of it. The love he felt for her had a way of starting to change his mind. Hormones took care of changing the rest of his mind. Mabel smirked at the growing redness in Dipper’s cheeks.
“There is a … tiny problem with tomorrow night, though,” Mabel continued, quietly and more seriously. “You need to get some …” she cleared her throat, “… condoms,” she mumbled.
The color of Dipper’s cheeks turned from red to a shade that was almost ashen in seconds. He remembered Mabel telling him the night they first made love that she had just had her period three days before. Quick math and recalling what he'd learned on the Internet about menstrual cycles proved that Mabel was right: she would be two weeks into her cycle tomorrow, the worst possible time for a girl to be unduly exposed to her brother’s sperm.
He stopped in his tracks on the sidewalk and gaped at his sister. “I’ve never bought condoms before!” he whispered urgently.
“Well, duh!” Mabel jabbed back affectionately. "Not the biggest surprise there, loverboy!”
Dipper wasn’t in the mood for joking around. He shushed her to quiet down, then continued in a low voice. “I mean, I don’t ... know how to get them! I’m only a kid, I can’t just walk into a drugstore and buy them, can I?”
“Uhh … yeah!” Mabel retorted in her own hushed tone. “You remember me telling you about Jordan’s sister, Kennedy? She’s only a year older than us, and she’s been buying her own condoms since middle school!”
“You also said everyone knows Kennedy’s a slut,” Dipper fired back, trying to keep his voice down, “and you were right! Even I knew she’s a slut!”
Mabel poked her finger to Dipper’s chest, and growled sexily under her breath. “Well, if you want tomorrow night to happen, you’re going to have to be my slut, dear brother!” She then gave him a playful shove with her palm.
Dipper recovered his balance and hovered near Mabel again. “Oh, c’mon! There’s no pharmacy anywhere near the school. Where can I go to where no one knows …”
A voice called out from behind them, accompanied by running footsteps. A girl, who Dipper recognized as Mabel’s friend Sandra, was sprinting towards them. “Maaa-belllll!” she was shrieking. Mabel turned to the approaching teenager, face lighting up. “Amper-Sandraaaaaaaa!” she screeched back, and ran to meet her friend.
Dipper held his palm to his forehead through his ball cap as the two friends reacquainted themselves. I’m going to have to figure this out on my own, aren’t I?
Mabel and Sandra quickly walked past Dipper and started to continue on their way to school, leaving Dipper standing there. Mabel turned as she walked. “C’mon, Bro Bro!” she called. “You’re gonna be late if you just stand there, Dippiter! You’re going to get those other things after school this afternoon, right?”
Dipper started walking after the girls. Ahead he could hear Sandra ask “What other things?” and Mabel’s reply of “I don’t know, just some nerd stuff he wants to get.” He shook his head, marvelling at his sister’s acting ability. His lover was temporarily gone, and air-quotes-Mabel was back.

Opening day at Piedmont High started off uneventfully for the freshmen Grade 9 students. Everyone found their class schedule. The twins noted that they had two classes together that first semester.
At lunch, Dipper met up with Ezra and Anthony, his two closest buddies from Grade 8, and got caught up on the latest gaming console titles and trading card games that their little crowd was into. Dipper’s friends also pressed him on the happenings in Oregon. They had been among the few who had taken seriously any of the stories of what had happened in Gravity Falls the previous summer, and both were heavily disappointed that Dipper had no new tales to tell following a second summer there.
Mostly, though, Dipper was trying to figure out where he was going to go after school to pick up his “supplies” for tomorrow night. He was also trying to figure out how to keep from getting hard-ons whenever he would think of the reasons for those supplies. It was almost impossible for him to not keep glancing to the table where Mabel and her friends sat halfway across the large room.
Mabel and Sandra found their other friends Jordan and Aisha, and a new friend Juanita. They were a decidedly multicultural group within the predominantly anglo school. Together they gleefully updated their group on their summer’s activities. They glanced around at the boys that passed by in the cafeteria, with many comments of approval on how hot the guys in the upper grades were. Mabel joined in this discussion, as she would have the previous year. She wondered how many of her friends were like her, putting on an act for the sake of the others, silently hiding their true lives and emotions.
Aisha was the most connected of the group to the older girls in the school, and she pointed out many of them and gave her friends a quick bio. Angelina was the likely head cheerleader and popular snob, don’t get on her bad side. Riley was into drugs and booze, but still kind of cool to talk to. Margaret was the driven, proper student, most likely to be valedictorian, doesn’t have a lot of time for anyone. Aisha knew almost everybody.
As lunch period came to a close, Mabel glanced across to where she had seen Dipper sit with his old friends. The twins locked eyes momentarily, and both of them smiled unconsciously. Juanita noticed the connection, and asked, “So Mabel, who’s that boy over there?”
Mabel had been thinking decidedly un-brotherly thoughts about Dipper at that moment, and she almost flushed. Sandra pounced on Juanita’s question. “Ooh, that’s her dork twin brother! Mabel doesn’t like to admit it, but she and Dipper are BFFs! It’s so sweet!” Sandra laughed as she dodged the friendly poke she knew was coming. She kept up her teasing of Mabel. “You seemed to hang around with him all the time last year, and you spent all summer up north with him again! Aren’t you sick of him yet?”
She glanced back to Dipper’s table, but he and his friends were walking away from their table. Outwardly indifferent, but thinking about Wednesday evening, she decided to answer truthfully. “Nope! He’s my brother, my best friend, and I love him!” she announced to her friends, eliciting a chorus of “Awww”s for her innocent-sounding proclamation.

Breathe slow, Dipper, he told himself again. You can do this! Man up!
Dipper was standing around the corner of the “family planning” aisle in the big CVS pharmacy down by I-580. He’d called his Mom at home, telling her he wanted to go the library after school, took the bus down Grand Avenue, and walked the rest of the way. It was not the regular drug store preferred by his parents.
He had surveyed the aisle sufficiently, walking down twice without stopping. The first time he located the shelf with the condoms, deciding on Trojans because they were the brand he recognized. The second time he tried to analyze the sizes and styles, and had no idea how to compare them, trying to read the labels while walking past them. He finally decided he’d just take the first box of Trojans he could lay his hands on.
Waiting until another shopper walked past him, Dipper took a deep breath and turned the corner. Had anyone cared to be watching, Dipper’s attempt at nonchalance would not have won any acting awards, but he managed to grab a box while knocking only three other boxes onto the floor. Securing a bag of potato chips to provide cover for the contents of his hand, he made his way to checkout.
There was only one register open, with a short line. This would be the hardest part: putting that box on the conveyor belt for the cashier and anyone behind him in line to see. He steeled himself and took his place.
It was about to be his turn, the customer in front of him was just unzipping her purse. The chips were already on the platform, the box ready to be placed, when Dipper chanced to look up at the entrance to the store. Walking through the automatic door was his youth pastor at church. Uhh, seriously!? Now? he thought desperately to himself.
Dipper lost all of his nerve. He left the chips on the belt, crammed the condoms into a box of chocolate bars beside the register, and swiftly made for the exit door before the pastor was able to spot him. He walked five minutes to the library, signed out the first Robert Hienlien novel he saw, and quickly boarded a bus back to Piedmont. He’d have to get this task done the following afternoon, before his parents left for their discussion group that evening.

That plan didn’t work out for Dipper. On Wednesday morning, the twins’ mother told them both to come straight home after school. She had come up with some new rules and responsibilities for the household for the new school year with the kids, and wanted to go over them. Since he had already signalled to Mabel that he had failed the previous day, Mabel was a touch irritated, but had no opportunity to say anything to Dipper. Sandra was waiting in front of the Pines’ house to walk with them to school.
Mabel, Dipper, Anthony, and Sandra walked home from school together, as they often had in years past. Anthony and Sandra had little in common, other than the twins as their friends, so when they walked it was generally the boys and girls having separate conversations. When Anthony turned off to his street, he asked Dipper if he wanted to come by after supper to play a few rounds of MtG with him and his brother.
“Thanks, but I think I’m supposed to stick around the house tonight,” Dipper replied, making sure that Mabel would overhear the comment.
Mabel heard. “You sure about that, Dipper?” she cut in evenly. “I don’t think you have to stay home.”
Dipper turned to look at his sister. There was no playfulness, no smile, only a neutral look. Anthony and Sandra thought it was nothing, just a girl correcting her brother on a fact of little importance. But Dipper now knew she was more than a bit pissed at him.
Looking directly at Mabel, Dipper responded, “Maybe I don’t have to stay home, but I want to.”
“Suit yourself,” Mabel replied, still poker-faced, then turned and continued with Sandra towards their home.
Dipper tried to appear normal as Anthony gave him a weird look. They said they’d see each other later, and Dipper walked off behind the girls. He hoped that he’d be able to patch it up with Mabel after their parents left for the evening.
For her part, Mabel couldn't handle dealing with Dipper anymore at that moment. She'd been holding off masturbating the last few days since learning of their upcoming time alone. Now her bottled up arousal and frustration were combining to make her angry with her brother. She knew better than to push things, as she was likely to say something that Sandra or her parents might overhear.

The rest of the afternoon dragged on tensely, but their mother didn’t appear to notice. Their father arrived home from work and the family ate normally. The parents asked if the kids could please clean up the dinner dishes for them, as they had to leave for their study group.
As soon as the car was out of the driveway and on the street, Mabel glared at Dipper.
“What was so hard that you couldn’t do just this one thing? Just buy a lousy box of condoms at a drugstore!” she grumbled.
Dipper was apologetic. “I’m sorry! Pastor Jim walked in as I was in line. I panicked!”
“So couldn't you have gone back again a few minutes later? Or just gone to another pharmacy?” Mabel sat on the living room sofa in a huff. “I just don’t get it! I’ve seen you fight zombies, a shapeshifter … you leaped off a cliff to rescue me from a giant robot! Why couldn’t you do this?”
“I don’t know!” Dipper groaned, rubbing his head. “Those were when we were in danger … but this was dangerous too, Mabel! Exactly what am I going to say to people who know me if they see me, of all kids, with a box of condoms?”
A small smirk crossed Mabel’s face. “You could tell them you met someone new at school … someone who likes you and you think may be special. And you want to be ready so you both can be safe!"
Dipper stopped and looked at Mabel. “You think anyone would really believe that?” he asked seriously.
“Yeah, they would!” The smirk grew to an evil grin. “Especially if you tell them his name!”
“Whose name would I … wait, what?” Dipper protested.
Mabel put on an innocent face, and said nothing.
Dipper sighed, seeing Mabel was toying with him. “Look, this skulking around just really freaks me out. I’m so scared of doing something that could cause us to get caught. I would just … Mabel, you know what Dad and Mom could do if they find out! I’d rather face anything that Gravity Falls ever dished out at us … than risk facing life without you,” he finished softly.
The irritation inside Mabel melted away with those words from her brother. Whatever his little failings, she saw that Dipper cared deeply about her and about their ability to remain together. It was hard to stay mad at him, it always was! She whined quietly and quickly got to her feet, stepping over to him and opening her arms. They held each other tightly, and Dipper whispered he was sorry again.
“I know you are,” she told him, “and I know how important this secret is. Maybe I shouldn’t push it, but it’s so hard! I love you so much, you big sack of mush!”
Dipper smiled and hugged tighter. “I love you, too, you silly … bundle of … ugh, whatever!” He pulled back, and he tenderly kissed his sister, their first kiss since they had arrived home. It was brief, but full of emotion. Dipper was aware they were standing in the middle of the living room, in full view of the street through the large window. “Think we should probably go somewhere without an audience?” he said, nodding at the street.
“Ack, yes!” Mabel replied sharply. She grabbed his hand and they dashed back to the bedrooms, choosing Dipper’s room because the door to his room was about a foot closer to the living room than Mabel’s.
When they were barely over the threshold, their lips came together again, then their whole bodies. As they necked, they clumsily shuffled to Dipper’s bed, where they flopped down together, laughing into each other’s mouths. Their urgency sated for the moment, they gave each other their favorite full-body, full squeeze hug, as they lay cheek-to-cheek in each other’s arms. (Mabel even had a name for it: the "not-so-awkward-sibling-hug". Dipper had yet to agree to the name.) Mabel fluttered as she felt Dipper’s erection pressing into her crotch through his pants.
“So I guess that was our first fight? As a couple?” Dipper asked, as they slightly relaxed their hold on one another.
“I guess so,” Mabel replied with a grin, rubbing her nose together with her brother’s. Then her expression turned faux-serious. “Too bad we don’t have any condoms, ’cause I hear make-up sex is the best!”
A sheepish smile crossed Dipper’s face. “Yeah, yeah! Sorry!” Mabel kissed him deeply to show there were no hard feelings, she just enjoyed giving him digs. Her hands roamed freely over his body, as she missed the feel of his body on hers. She wondered how she would ever get used to not being able to feel her brother next to her.
But for now, she would take advantage of how close they could be to one another. Propping herself up quickly, Mabel took off her sweater and shirt, prompting Dipper to do the same with his own t-shirt. Dipper loved Mabel’s breasts and the reactions he could get out of her from them, and he gazed at her chest hungrily. Her mounds were small and firm, not requiring a bra when Mabel wore her trademark sweaters. Dipper knew from experience that her nipples were very sensitive, and she loved it when he gently used his teeth on them. He gave them a soft squeeze, and pinched her nipples lightly, drawing a wonderful-sounding gasp from Mabel. Then they lay back down again and resumed their kissing, satisfied to resume their foreplay with delicious skin-to-skin contact.
Dipper’s hands moved over Mabel’s torso with an expertise that belied his lack of experience. Though they had fewer than a dozen sexual encounters up to that point, he had paid close attention to Mabel’s reactions and what triggered them. He used his palms and fingertips in different combinations, light touches and firm strokes, in different places. Combined with the slow grinding of their clothed hips together, he not-so-slowly worked her arousal up.
Mabel knew it was a little more difficult for her to return the favor. Dipper was still intensely ticklish, and she had learned last week that it kind of interrupts things if your lover suddenly convulses and shrinks into a fetal position as you are caressing him. The palms of her hands were fine, but that left her feeling that Dipper was being underserved. Mabel decided he needed some help further down, so she slipped her free hand down between them and started massaging on the hard protrusion in his pants.
A groan arose from Dipper as Mabel started rubbing up and down, squeezing his penis through his clothes. For several heartbeats, he increased the pace of the movement of his hands on her body. Then he froze, as he felt a rapid tightening in his groin. He broke the kiss as fast as he could. “Mabel, stop!” he cried desperately, but it was too late.
Mabel stopped cold in momentary confusion as Dipper tensed, and moaned “Noooooo!” through his teeth. Then Mabel felt his penis pulsing in her hand through the fabric, and she knew what had happened.
Mabel had stumbled on something that Dipper had been trying to hide from her. He had a bad case of premature ejaculation, something not exactly rare for an over-stimulated boy just turned fourteen. It had happened their first night together, and since then Dipper had been secretly masturbating prior to their lovemaking. He’d not raised any suspicions from Mabel because with his near constant state of arousal, it had never taken him longer than a minute or two in private before he was done. But on this evening, he was so distressed over Mabel’s anger that the task had never occurred to him.
After the embarrassing deed was complete, he opened his eyes, but didn’t want to look at his sister, and gingerly started to get up. Mabel held him firm, and pulled his face to hers. Her expression showed amusement more than anything, but that didn’t make Dipper feel any better. She opted to replace humor with compassion. She pulled him close and whispered to him that it was all right. Shamefully, he explained what was wrong, and what he had been doing.
“I wish I didn’t have to … get off like that first,” as he continued his confession, “but it makes things so much better, Mabel! I’m able to keep going so much longer with you after I’ve … taken care of myself first.”
“Dipper, you don’t have to do that alone! I’d love to … you know, help you with that!” she assured him, and she plainly meant it.
Dipper did feel a bit better to know Mabel wasn’t put off by the revelation. Still, he screwed up his face as he awkwardly started to get up off the bed. “Be careful what you wish for, Mabel,” he grimaced. “This is really gross! I have to go to the bathroom.” He walked bow-legged into the hallway.
“I have seen that stuff before, you know!” she called, following him out of the bedroom. “You’ve put quite a bit inside me, if I recall correctly!” she added, laughing.
“You’ve been getting round two,” Dipper replied quietly as he carefully pulled his pants and underwear down in front of the sink, then he grabbed a washcloth from a shelf and wet it. “Do you have to watch this?” he complained, exhaling loudly at Mabel’s wide grin and enthusiastic nod. Resigned, he reluctantly continued, “Trust me, I know how different it is. There’s a lot …” he gestured to the mess, “... more … here than I’ve been giving you. I have a lot less stuff the second time, and takes me a lot longer to get there, but it feels way more intense when it happens.” He made a face as he started wiping himself clean.
“Oh, so you’ve been giving me substandard product?” Mabel joked. Dipper groaned at her as he continued to wipe up semen. She beheld her brother, spunk-filled underwear and pants at his ankles, knees spread, pelvis extended, bent over, and wiping his sticky crotch. She crossed her arms over her bare chest and leaned against the doorframe. “What a beautiful vision to have burned into my brain!” she smirked at him. “Where’s that memory eraser gun gone to?”
Dipper continued in silence, not enjoying Mabel’s barbs. He finished drying himself off, then completed the job of undressing himself, trying to prevent the semen in his clothes from getting all over everything. Now naked, he stood in front of the sink washing out his underwear, thoroughly deflated both emotionally and sexually.
Mabel’s smirk softened to an affectionate smile. Dipper was being all sucky again! She crept up behind her brother and wrapped her arms around his waist from behind, resting her chin on his left shoulder. Dipper unconsciously relaxed, closing his eyes and leaning his head back over to hers. She smiled at their reflection in the mirror. For all the differences in their personalities, she loved how alike they were as well. Like how they knew each other enough to not only get under each others’ skins, but also want to press their skins together.
Dipper let go of his frustration with Mabel’s rapid back-and-forth swings between gentle empathy and making jokes: it was just part of what made her Mabel, the girl he was in love with. He opened his eyes and looked back at his and his sister’s image in the reflection in front of him. They were both still about the same height, so their heads were nestled together perfectly.
They had never seen themselves together like this, looking at faces that they had seen smiling back from countless photos, but never before in such an intimate embrace. Yes, there was an obvious family resemblance, no one would ever think they weren’t brother and sister to see them. The same round shape of their faces, their large and expressive dark eyes, small noses, and thick brown hair: they were cut from the same cloth. Dipper wondered if any photos of themselves from now on would capture the change that had come to them. Mabel wondered if a couple could look any more adorable together, and she reached up around to gently poke her finger in Dipper’s right cheek. Dipper guided his left hand to Mabel’s left cheek to return the gesture, Mabel giggling as he narrowly missed poking her in the eye.
Mabel pulled Dipper into herself firmly and pressed her breasts harder into his back. She guided her hand back to his torso, moving it slowly over his nearly-hairless chest and stomach. Dipper tensed and started shaking with suppressed, uncomfortable laughter, allowing Mabel to teasingly walk the fine line between tickling and caressing. With her other hand, she had unzipped her skirt, and was deftly dropping the remainder of her clothing to the floor. After kicking her clothes away, she then turned him around and they easily slipped their arms around each other.
Suddenly, Mabel perked up. "Well, that little adventure in sexual self-control is done!” Mabel declared. She transitioned to a truly terrible British accent, and proclaimed, “After conducting thyself with the g-drdrdrd-randest dignity, I shall knight thee! You shall be named ... Sir Dipshit, of the Court of Came-a-lot!” Mabel grinned widely at her dorkus of a brother.
Dipper shook his head in wonder, trying to determine if he should be amused, or try to feel offended. The look on his sister’s face tipped the scale, and his chest was shaking in stifled laughter as Mabel leaned in to press her tongue into his mouth.
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Fistbump 2: Unspeakable (a Pinecest story)