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Awkward Sibling Hug	By : ShadowProc213 Category: +G through L > Gravity Falls Views: 13372 -:- Recommendations : 0 -:- Currently Reading : 0
Disclaimer: I do not own Gravity Falls, nor the characters from it. I do not make any money from the writing of this story.

Chapter List
- 1-Awkward Sibling Hug
- 1
Dipper and Mabel had done the 'sharing a room' thing until they were twelve. Namely, Mabel got her own room just as soon as her chest started budding.
The Pines Parents, Joseph and Beverly, had gone to a great deal of trouble to ensure that their children didn't stray onto the wrong path. They sat them both down and gave them the sex talk when they were caught playing 'doctor'... at the age of five. Didn't even take them into separate rooms. It held a place in their collective memories as the most humiliating moment in their lives until they spent a few summers with Grunkle Stan and got to know just how much worse it could get. Mabel could still remember the horror of Stan explaining how the pituitary gland worked; it was almost like that conversation brought back some of the traumatizing humiliation from the first talk... then compounded it.
Those were still nothing compared to this moment. The night had been planned out perfectly. Joe and Bev were supposed to be gone all of Memorial Day weekend, and that gave dipper the chance to cook up something extra-special for his dear sister. After they ate up the chicken that Dipper had cooked, they both tore off their clothing in record time.
Dipper and Mabel were rolling around on the floor of Mabel's bedroom, their mouths locked together, and their tongues sliding across one another. They rolled into a shelf, knocking over a glitter-sculpture, and sealing their fate.
They hadn't heard the door opening, but their parents had come home early. Truck-stop sushi had tainted yet another person's perfectly good road trip. And when she heard the shattering ceramic, Beverly did what any good mother would do. She swung the door open, and had her eyes filled with the image of her children in a carnal embrace.
The screaming, from everyone, had calmed down. But there was no unseeing this for Beverly. She sat them both down in the living room, and dragged her poisoned husband to the master bedroom. When she sat down in front of them both, Dipper had gotten some jeans on, and Mabel had thrown on her most over-sized sweater. Beverly took a few deep breaths, and tried to confront this logically. After all, she was an architect; if she could fix a ten-story library downtown, then she could definitely fix this.
"Mabel, I know that you're usually the passionate one. Now, can you tell me what you were thinking while you were seducing your brother?" Beverly asked, doing her absolute best to crush that sense of disgust that was in her stomach, and keep eye contact with her daughter.
"I wasn't thinking, I was feeling; and I was doing what felt right." Mabel couldn't talk... it was a strain just to maintain a sentence. But she could blurt whatever came into her head.
Dipper, on the other hand, shared his mother's amazing sense of both logic and composure, though he'd taken some time to grow into it. What had started as a child obsessed with conspiracies had evolved into a real forensicator, with the linguistic skills to match... "We don't have to justify, rationalize, or suppress this relationship. Mabel and I took a long time to come to terms with it, but it's for the best."
That was it, an opening that Beverly felt she could use to appeal to Dipper's sense of logic. "You think it's what's best? Fine. We can play that game, Dipper. How far have you thought this out?"
"Six Years." He sniped. "Things get hazy in the years after college."
"I admit, that's about five and a half more years than I'd give normal teenagers credit for. What about eight years from now, when you want to have a baby. Or were you planning on having an inbred baby?" Beverly demanded.
"I turn eighteen, get a vasectomy." Dipper smiled. "Freeze some sperm, in case Mabel gets a demanding job. She doesn't get a job, we can have a child with a sperm donor. She does get a job, we use a surrogate. Simple."
"I must admit, Dipper, I'm proud of that plan." Bev smiled. "Now, let's back-track. Next school year, how are you going to keep this a secret?"
"How long do you think we've kept it from you?" Mabel smiled with those wonderfully straightened teeth.
"What are you talking about?" Bev demanded.
"Dipper and I have been together for the past three years." Mabel explained, finally regaining some of her senses. "The only reason you even noticed is because of a fluke. The two things that keep our secret safe are, A: The fact that people already expect twins to be creepily close, and B: The fact that we've learned how to be genuinely cautious."
"You two were about to have sex! That's not cautious at all!" Their mother screamed at them.
"No. We weren't going to have sex." Dipper shot. "Give yourself some credit. You raised us with more than enough self-restraint not to start fucking like rabbits just because our pants are off."
"Don't try to make me feel proud. I'm busy trying not to vomit." Bev scolded.
"Don't talk down to us about this!" Dipper shouted at her.
"I'm not judging you right now, it's--" She didn't even finish the sentence, she just fell unconscious after purging the sushi.
Dipper turned to Mabel. "What do we do now?"
"Set them both down in their bed, and hope they both think it was just a food-poisoning induced hallucination?" Mabel asked back.
"Okay, just... clean up the floor. I think I can spot some whole pieces that she just tossed back." Dipper commented, dragging his mother off.
"Yeppers, she definitely needs to chew her food better." Mabel thought aloud.
Not too much later in the week, the two of them decided to head out for their annual trip to Gravity Falls. It was always nice to reconnect with people, though some of the people that Dipper reconnected with each year had a tendency to try to kill them both... repeatedly.
Every time they'd arrived in the Mystery Shack before, Dipper and Mabel's Great Uncle Stan had greeted them with an oddly passive addressing of their existence; then telling them that, if they wanted to do anything in Gravity Falls, they'd have to do it on their own initiative. He usually did this with simple expulsions like, "Stop buggin' me." or "If you're gonna yap, then sweep the floor."
Today, though, he was standing standing there, waiting for them in the front room. "So... Dipper, Mabel, your parents were very concerned when they called me yesterday. They were talking about some crazy thing involving hallucinations and it got me to thinkin'. So I gave your collective room a little upgrade."
"You didn't install cameras, did you?" Dipper asked.
"No, I had the old ones removed!" Stan joked. "Aw, come on. That's hilarious!"
Mabel was already at the top of the stairs, looking through the trap-door to the attic. "Hey, Dip. You've gotta see this." Dipper chased her up the stairs, standing beside his dear sister, and saw that the tiny beds had been removed. His side of the room was now filled by a queen sized bed with a drywall section there to divide both sides of it, and the outer walls were covered with bookcases, all except for those two gaps where there were windows to let in some light. Mabel ran over to one of the bookcases, and scanned her way across a few of the shelves. "There are all of our old scrapbooks, plus your stuff on conspiracies, plus-- is that shelf full of Kama Sutra?" Mabel yelled in shock.
"Don't be silly, Mabel-- Wow, that's a useless sentence if ever there was one-- there's stuff in there about the psychology of human sexuality, some stuff about classes taught by some... specialists!" Stan was an expert charlatan. If he could keep up the energy in his pitch, then they wouldn't notice the flaws.
"Grunkle Stan, there's a fine line between being supportive and being creepy. You jumped that line about fifty miles ago." Dipper said, glaring down the stairs.
"Dipper, I think some of these books got misfiled. The stuff about criminally sexual deviants is next to the murderers on the fourth shelf, but there's a whole section on ways to improve the appeal of a woman's privates on the third shelf. Shouldn't anything regarding self-mutilation be in with the criminally insane stuff?" Mabel thought that all out loud, clearly pointing out where the labels were on shelves and where the books sat. Dipper was truly impressed. He would have given her a pat on the back, possibly even parlayed it into a kiss, but there was a paternal authority figure, flawed though he may have been, standing right there.
"Well, when I heard your mother tell me about her dream, I thought it was worth trying to be nice." Stan said to Dipper, setting his eight-ball cane against the wall. "After all, she seemed really upset."
"She'll get over it." Dipper assured him, walking the rest of the way upstairs.
"She thinks she's going crazy." Stan warned, his tone shifting into something stern.
"And, by the end of the summer, she'll have forgotten all about it." Dipper assured him. "Besides, where are you sitting on the judgment of her little delusion?"
"You two should keep things under wraps. Not everyone is as understanding as me." Stan reminded, flipping his eye-patch down. "Oh, and by the way: the divider on the bed is removable."
Dipper closed the trap door after him. Sitting down on the bed, he looked at Mabel. "Stan knows. He figured it all out from a raving presumed food-borne hallucination, but he knows." Dipper started breathing rapidly.
Mabel pulled one of the books off the criminology shelf and handed it to Dipper. "Here you go, bro-bro. Take some nice, even breaths and read about Albert Fish. Reading about psychopaths always calms you down."
Dipper closed it after the first few paragraphs. "This is too much. If Stan knows, what's to keep him from telling Mom and Dad?"
"Because it's Grunkle Stan? He never lets his secrets slip. He's Mister Super-Conspiracy, just as much as he was in the old days. The only difference is that now we don't have to hide from him. That's a net positive."
"What about everyone else here? This isn't like back home. Around here, everyone has secrets, and that just makes them all more paranoid." Dipper stared at the back of Mabel's head while she thumbed through one of the books filled with sex suggestions. "Just the gossip from the girls here will burn us."
"Most of them... aren't that perceptive." Mabel laid back on the bed, holding up her book. "Take a look at this. It says if we do it with me facing away from you, we can hit something called a g-spot." Mabel teased.
"Shouldn't we wait until we've had a first time before we start spicing things up?" Dipper asked, turning back to the bookshelves.
"The reason why so many of those married couples' sex lives go stagnant is because they wait too long to be creative with their intimacy." Mabel argued. "We should really get a jump on it."
"Just like I explained to Mom, I don't plan on actually having sex with you. At least, not yet." Dipper dragged his finger along the spines of these books, feeling the mix of dusty leather hardcovers and shiny smooth paperbacks.
He knew there was another mystery here. There were dozens of them, every year, and he couldn't afford to get distracted from his mission. Focused like he was on that mission, and its indeterminate goal, he didn't even notice all the noise behind him as the fabric on the bed rustled and shifted. He heard a few footsteps approaching behind him, and a hand on his shoulder. "Mabel, I'm not going to--" he went silent as she held up a finger to his lips, and saw that she was completely topless, his eyes drawn mostly to her petite breasts and her neon pink hair ribbon.
"You need to have just a little bit less self-control." Mabel teased, sliding her hand down the front of her brother's pants. "Oh, I feel that, so happy in my hand. You're so excited, but you're going to keep our little friends down there from playing together." She whispered, repeatedly kissing his neck. "Don't you think my Little Mabel deserves to feel your Little Dipper for the first time?"
Being with Mabel had really brought Dipper to a greater level of integrity, but it hadn't made him incorruptible, and it had left his highly passionate sister much more able to influence him. He tried to put together an argument, even a reason why they should stop. Instead, he started flirting, "What do you mean 'Little Dipper'?" He teased, his hands sliding around his twin sister's waist.
"Well, my bro-bro is clearly the Big Dipper," Mabel teased, kissing him on the lips, "and the Little Dipper down there is definitely smaller than him, though it feels awfully big in my hand..." she smiled. Unbuttoning his jeans was pretty easy, Dipper managed to swiftly toss off his shirt, and his hat went with it; and Mabel's pants just slipped right down her thighs when Dipper applied a little pressure, and exposing her tight-cut briefs to his groping, tickling fingers.
Mabel began giggling at the feeling of his fingertips getting past the elastic of her panties, dancing over the gentle curve of her butt, all the way down in between her thighs. "You feel so 'excited', too." Dipper whispered back, and kissed his sister again. His pants and boxers were already on the floor, so he just pushed her panties down past her thighs. Now both completely naked, Mabel wrapped her arms around Dipper's torso, pulling him along as she fell back onto the bed. They both fell away from that pile of clothes on the floor, their naked bodies slapping together as they hit that mattress.
Of course, Mabel didn't mean for the next part to happen, and the shock that it brought forced a gasp as her sweet twin brother's erect shaft slipped so quickly, so smoothly inside of her. She felt it filling her up so perfectly and so completely, and his mouth was so close. Mabel just wanted to kiss her dear Dipper, but knew that this was an accident. "Dipper... is this a mistake?" She asked, still embracing him, and hoping that he'd stay right there.
"Probably." Dipper answered, but not pulling away. He only pulled out a little, then thrust in again, and kissed Mabel lightly. "Do you want it to stop?"
"No." Mabel breathed, kissing her brother back as she brought her hips up to meet another slow thrust, delighting in the squishing noises that they made as they pressed themselves together. "I just want to stay here, with you, for as long as we can." Mabel kept up that rhythm, squishing herself together with her twin. "This just feels so perfect..." she trailed off as she kissed him again, slipping her tongue in to taste his teeth, lingering on that minty 'I floss way too often' taste in his mouth.
Dipper wasn't the type to do anything mindlessly, but he had left any rational thought behind with that pile of clothes on the floor. He would thrust into Mabel, and she would try to pull him closer, leaving those pink scratches on his shoulders as she clawed into her brother. He felt her writhing beneath him, and she kissed upward and pulled herself up to him with her heels hooked around his hips.
Mabel and Dipper both flipped over, trading positions. Dipper was now laying under Mabel, her hands gently pinning his wrists and her tongue aggressively tasting the inside of his mouth. She broke their kiss and rolled her hips atop him; it wasn't getting Dipper's face looking nearly as happy as he did on top of her, but he did still look happy, and it felt great for Mabel as she felt his member all over her insides. When she felt it at one particular spot, her eyes rolled into her head and she arched her back as far as she could, trying to get her brother to 'poke' her there as hard as he could.
As Dipper looked up, watching his twin sister riding him, he smiled at her, "You're so beautiful up there." He commented, and that's when she leaned back, and she arched her back, making a little squealing noise, but dragging out that squeal across several seconds. "You wanna try that thing from your sex book?" he asked.
Mabel pulled herself away, just far enough to flip herself over on top of Dipper. Now laying on her back, on top of Dipper's belly. She took hold of his fleshy Little Dipper between her thighs, and pressed its tip to the lips of her Little Mabel. Her brother pushed upward reflexively, forcing Mabel to sigh deeply as his shaft scraped along the front-most part of her inner wall. Until this moment, she hadn't understood the importance of a g-spot, but she felt the need to scream in pleasure. Of course, the pillows were under Dipper, so she turned her head as best she could, grabbing Dipper's head and kissing her brother lovingly, Mabel's moaning muted by his mouth covering hers.
Dipper resumed thrusting into his sister once more, his right hand trailing down her waist, finding its way to delicately greet his sister's own right hand. Their fingers were touching together, not quite intertwined, rubbing Mabel's soft and sensitive clitoris. Reaching up, he began likewise rubbing and fondling her left breast with his left hand, pinching the nipple between his middle and index finger, not hard enough to hurt her, but hard enough to make her shudder atop him.
This time, when the thrusting stopped, it wasn't just because one of them had chosen to interrupt their erotic dance together. Mabel felt it as Dipper shot sticky strands of loving semen inside of her. She knew it was a bad idea, she knew it was wrong, but as Dipper drifted off, barely able to whisper out one more "I love you so much." before his eyes closed; Mabel decided to just lay there, kiss her brother's forehead, and relax to the feeling of his sticky love oozing throughout her innards, even seeping from her pussy once his rapidly softening member flopped out of her. She decided to just stay there, with her loving brother, until she fell asleep as well.
- 1
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Awkward Sibling Hug