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Fistbump (a Pinecest story)	By : Edward_or_Ford Category: +G through L > Gravity Falls Views: 13063 -:- Recommendations : 1 -:- Currently Reading : 0
Disclaimer: I do not own Gravity Falls or its characters. I will not earn any money from this story.

Chapter List
- 6
- 7
- 8
It was after one in the morning by then, but for the Pines twins, they were no longer feeling tired at all. It was like they had tapped into an oil well: the pressure was released, and their passion started to erupt.
Neither of the twins were very experienced with kissing: they each only had kissed one other person, and both of those were innocent, closed-mouth smooches. Now with the feelings of long-suppressed love urging them on, Mabel and Dipper wanted to figure out how to make kissing more pleasurable. Both knew about French kissing, but neither had tried it.
Mabel opened her mouth first, silently encouraging Dipper to try it, too. Soon they were wrestling their tongues together like pros, while their hands rubbed up and down the backs and necks of their partners. Their bodies were pressed together as tightly as their lips, though still seated awkwardly on the end of Dipper’s bed.
They broke apart, both gasping for breath.
“Wow!” panted Mabel. “That’s really nice! That makes me feel so good!”
Dipper was also in awe. “Everything about you is wonderful … I love you!”
Mabel shivered with delight hearing that. She planted another urgent kiss on his lips. “That means I love you, too!”
They rested their foreheads together. Dipper ran his hand through Mabel’s hair and caressed her face, and she hummed happily. They stared into each other eyes again.
Suddenly Dipper was uncertain. “Mabel? Are we … is this … okay?”
“I don’t know,” Mabel replied quietly, looking down. “I know we’re not supposed to do this.” She looked back up to his eyes. “I’m not supposed to feel this way. But I do!”
“I do, too!” Dipper said with certainty. “I think I’ve felt this way a long time, but I just didn’t realize it.”
Mabel shifted, backing away enough to pull her right foot up onto the bed and rotate her body to face Dipper more comfortably, but kept her arms firmly around Dipper’s neck and back. “So when did you realize it?” she asked him.
“Just tonight,” he told her. “When we were in the river at the waterfront. When I was trying to make you get up.”
Mabel’s expression turned stricken. “When you were crying! I completely forgot about that! I’m so sorry!” She pulled his head towards her and kissed Dipper’s forehead.
“It’s okay. Really! If you hadn’t been in that state I might never have realized how I feel about you.” He kissed her lips gently. “What about you? When did you see this?”
“Oh, I was way ahead of you!” Mabel said proudly. “I had it all figured out way back … to this morning!”
Dipper smiled at the revelation that they would both discover their love on the same day, then thought a little more about what Mabel had said. Then his eyes widened, and his mouth formed a small “o”. “Wait a minute,” he said slowly, then his smile started to return. “In the shower, this morning?” he asked slyly.
Mabel’s hand flew to her mouth as her eyes grew wide with embarrassment. “You did hear me!” she cried in a hoarse whisper. “What did you hear?”
“That you had a really great time, mostly!” Dipper retorted, as he turned his body as Mabel did to make himself more comfortable. Mabel blushed, and Dipper grinned at her discomfort. “This serves you right, after all the grief you gave me today.”
“Oh, shut up!” Mabel shot back, forcing the issue by leaning forward and occupying Dipper’s mouth with her own.
Mabel was even less inhibited now. Knowing that Dipper had heard her in the heat of her greatest passion, made her feel even hotter. She wanted to feel more of Dipper, to feel the comfort of the touch of his body to hers. But the way they were seated on the bed, their legs were keeping their bodies from pressing together, and they were both leaning forward uncomfortably.
She first maneuvered her hands to Dipper’s chest. Then with the speed of a cat, Mabel pushed up with her legs and forward with her arms, shoving Dipper down and rolling him over so that he was on his back, and Mabel was now laying on his chest. Though Dipper’s eyes grew wide and he grunted out amused alarm, their lips remained locked. Mabel groaned with satisfaction as she started getting comfortable on top of her brother.
The closeness of the embrace, the weight of their bodies together, caused the twins to more fully feel the impact their new relationship, of what they had been missing all this time. They reduced the frenetic speed of their kiss, pressing their mouths harder against one another, all the while holding each other tighter and tighter. They finally ended up with their cheeks pressed together and squeezing each other together as hard as they could, eyes moist, whispering “I love you” into the other’s ear over and over again.
Dipper decided that his questions about the morality of their feelings could be set aside for now. This felt too good, for both of them, to question this now. He knew his love for Mabel was genuine, and he wanted to make sure she knew it.
Mabel was even more committed. As they laid tight in each other’s arms, she silently vowed that Dipper would be her first lover. She had no reservations. She could imagine no one else who she would want to give herself to. She didn’t care when or where, but she knew that he would complete her.

The intensity of the moment passed. Mabel relaxed her grip, and kissed Dipper’s neck.
Dipper continued to hold on to Mabel tightly, but for other reasons now. “I don’t want to break the mood,” Dipper said smiling, “but I think we’re about to fall off the bed.”
Mabel lifted her head and looked around. Sure enough, when she had pushed Dipper down, he had rolled off to one side of the bed, and because of where he was sitting, his feet were still on the floor over the end. And as they were in the middle of the squeeze hug, Mabel hadn’t noticed they were shifting down further down to the corner of the mattress.
As Mabel started to get up off of Dipper, he became aware of how worked up all this had made him. He had been filled with love, wonder, and joy: he had not thought of anything specifically sexual. But his body obviously had been observing what was going on. His penis was fully erect and ready, and as Mabel’s weight lifted up, the evidence of his arousal beneath the bathrobe was plain to both of them.
Dipper’s reaction was to again be embarrassed and remorseful. For all they had just done, he hadn’t even been thinking of what more they could do, but the tent pole beneath the robe indicated that he had been. He was positive that Mabel would be grossed out, and he had promised her it wouldn’t happen again! He sat up quickly and tried to push it back down, hanging his head shamefully.
Remembering his meltdown at the museum, and knowing that this was a touchy thing for Dipper, she crouched on the bed beside him and grasped his hands, pulling them away. “No, it’s okay!” she said softly, looking at Dipper’s face instead of his crotch. “I don’t mind!” she continued, squeezing his hands.
Dipper turned to look into Mabel’s eyes. It was okay! He couldn’t believe that she wasn’t disgusted by him. Fleetingly, he thought about how a sister was supposed to feel about her brother, and then he accepted it again. He didn’t want to ruin the moment.
Mabel leaned forward and kissed Dipper softly, twice, then a third time. Then she backed off an inch. She knew she was ready to go further.
“Dipper,” she asked gently, “can I … see it?” lowering her eyes down then back up again quickly.
Dipper swallowed. This was going very quickly, far more so than he could have expected, had he even ever expected any of this to happen. But for the life of him, he could find no reason to object to her request. He nodded imperceptibly, and managed to breathe out “… ‘kay!”
Mabel slowly got up off the bed, still holding Dipper’s hands. He was still seated on the corner of the bed, so she gently tugged him to his feet and guided him over to the middle, where she sat him back down again. Putting a knee on the mattress, she pulled Dipper’s arms apart and pushed him back a bit further, then let him go so that he was reclined back with his elbows supporting his upper body. Mabel looked down and again saw the protrusion beneath his robe, and felt a fluttering sensation in her abdomen.
Getting back off the bed, Mabel stepped in front of Dipper’s legs and got down on her knees. She wanted to get a good look at him. She had vague memories of bathing with Dipper as a small child, but this would be the first time she would see him like this, and she wanted to remember every detail.
She reached up and touched the knot holding the bathrobe closed, then as she pulled the knot apart, she heard Dipper’s sharp intake of breath. She looked up and loved the look of awe, mixed with stark terror, on his face. The knot now loosened, she lifted one side of the robe off, exposing Dipper’s left side completely. Mabel gazed lovingly at Dipper’s almost hairless chest, and her eyes moved to his bare hip and upper thigh. She ran the tips of her fingers up his leg and over the hip, up to his waist and chest. Dipper tensed and hissed several times, the tension and his ticklishness (now deliciously uncomfortable) combining to overwhelm him. Mabel’s smile widened, knowing that she was making Dipper feel good.
Slowly, she lifted the other side of the robe off, now fully seeing her brother’s naked body. She stared in wonder at Dipper’s penis. It was about four or five inches long, pointed straight up. It was jerking slightly, obviously in tune with his pounding heartbeat. It was uncircumcised, but the skin at the tip was slightly open, and a drop of clear fluid was forming there. The penis was smooth, and the sack at its base was a bit wrinkly and nestled tight, right beneath it, with just a bit of hair. He also had some soft, fuzzy hair at the base of his penis. She thought it was all beautiful.
Mabel’s right hand moved back down from Dipper’s chest to the newly revealed organ, making Dipper squirm. Agonizingly slowly, she ran a finger lightly up the length of the shaft on one side, then back down the other side. She repeated the process in reverse with another finger. Dipper’s breathing grew laboured.
Mabel somehow had an instinctive knowledge of how a penis should be handled. Her left fingers gently caressed his scrotum, while her right hand closed around the shaft, marvelling at the heat of it, and how soft, yet hard, it was. She loved its shape and smoothness. She wanted to see the tip a bit better, so she gripped a bit and pulled down slightly.
Dipper had been hovering on the edge for several moments now. Mabel’s examination had been exquisite torture. Masturbation was one thing, having the girl of his dreams touching him was quite another. And now, one jack downward by his sister on his penis, and he was gone. His hips thrust upwards, and he gasped out “Ma … Mabel!”, then his body went tense and he winced loudly.
Eyes wide, Mabel felt Dipper’s testicles pull tight. His penis throbbed hard, then she watched awestruck as a long rope of milky semen fired out into the air. It hadn’t even landed on his leg and robe when another spewed out: it had less force and splattered on her left hand. She watched amazed as his penis continued jumping in her hand and more semen pumped out the tip, over the shaft, and down over her thumb and fingers. His anguished cries sounded more like pain than pleasure. She had no idea a boy’s orgasm was like this!
Soon enough Dipper’s premature climax was finished. He struggled to regain his breath and composure. He had just blown his load after a grand total of fifteen seconds of actual stimulation. He collapsed onto his back, hands over his eyes and forehead in fatigue and shame.
Mabel didn’t share his negative mood. “Wow!” she enthused. “That was amazing!” She examined her wet and sticky hands, sniffing experimentally. “Pretty messy, though! Do you do that all the time? How do you keep from getting it all over the place?” as she found a towel she had used to dry her hair and began wiping up the semen.
Her nonplussed mood surprised Dipper. He thought she’d be disappointed in him. “Uhh, I … yeah,” he stammered. “That’s the way it goes. That was a …” he blushed, “a pretty strong one, though.” Mabel smiled, pleased. “And usually,” Dipper blushed again, “I use a bunch of tissue, or toilet paper … Keeps things from getting messy.” He thought it odd that he had just ejaculated all over himself and was now completely exposing himself in front of his sister, but he still blushed when discussing his masturbatory history.
Then he figured out that she didn’t know boys took a while to recover after an orgasm. Mabel was using her towel to clean up his penis and groin of the mess, and he noted that it was already beginning to go flaccid.
“Yeah, so … I’m going to be kind of useless for a while,” Dipper said sadly, as he took the towel from Mabel and finished wiping up.
Mabel looked concerned. “I didn’t hurt it, did I? It sounded like I was killing you!”
“No. No! It was really, really good!” Dipper reassured her. “But when a guy comes … it kind of goes soft whether he wants it to or not. It takes a while to be able to do anything again.”
Mabel looked at him craftily. “How long?” she asked.
Dipper gestured helplessly. “I don’t know, I never put a stopwatch on it!” he protested.
“Well, then,” she said softly, “you have time on your hands for other things? You’re not completely useless, right?”
The fog over Dipper’s brain lifted, and he realized her innuendo was right. He could do things for Mabel, as she had done for him, and his penis wasn’t required for any of it.

He raised himself back up to a sitting position while Mabel sat down beside him, pushing the robe off his shoulders and arms, back down to the bed. He felt vulnerable, yet so comfortable, being completely naked in front of his sister.
Their lips found each other again, and their arms found each other’s bodies. Mabel explored Dipper’s bare skin from his neck to his butt and back up again. Dipper’s hands stayed outside Mabel’s robe, as he was still shyly waiting on a sign from Mabel on what she wanted him to do.
Mabel took Dipper’s right arm and grasped his hand. She placed his palm on the exposed part of her chest, just below her neck. Dipper understood that she wanted him to make the next move. Through their kisses, he took a deep breath. He would soon be able to see and touch those perfect breasts.
Dipper slid his hand across to Mabel’s left arm, pushing the robe down over her shoulder. She moaned in his mouth, signalling her approval. His left hand came around to address the knot on her robe, and with a single pull it was loose. Mabel released her hold on Dipper with her left arm, and almost on its own, the robe fell away from the left side of Mabel’s torso. She broke their kiss to pull out her arm from the sleeve and let Dipper see her exposed breast.
It was as beautiful as Dipper had remembered from that morning, through the static cling of the t-shirt. Tentatively, he caressed around its lower edges, and ran his thumb over the nipple. Then he cupped the whole breast and gently squeezed. Mabel cooed satisfied sounds. Gently Dipper lowered the other half of the robe from Mabel’s other shoulder, giving him access to both of her firm mounds. Looking back to Mabel’s face while massaging her, Dipper gently pinched her nipples, eliciting a priceless series of noises, facial expressions, and body tremors from his sister. He let her reactions guide him as to what felt good for her.
As Mabel squirmed around, her robe pooled around her waist, leaving her as naked as Dipper. He was eager to see what awaited him between her legs, but again he waited on Mabel to guide his progress. Instead, still seated beside each other on the end of the bed, the twins pulled each other’s bodies against one other and their kissing resumed. They thrilled in the new sensations of all-over skin-to-skin contact, and their hands roamed freely. Their breathing was growing ragged as the strokes of their fingers and palms moved faster and firmer across each other’s nude bodies.
Suddenly, Mabel snatched Dipper’s right hand and pulled it between her legs. Dipper’s head pulled back from their kissing and they both looked down as Mabel tried to guide Dipper’s fingers to where she wanted him to stimulate. He started to explore her smooth privates, but the angle was wrong: they were partly turned toward one another, so in order to use his fingertips, Dipper had to try to awkwardly twist his wrist, and he wasn’t able to get it turned enough. Mabel tried to help by turning her body to the left, but that left her weirdly sideways to Dipper’s embrace.
Mabel quickly said “Just a second!” and untangled herself. She stood up, allowing Dipper to fully see her body for the first time. She was gorgeous, absolutely beautiful! She had no hair between her legs at all: she would tell Dipper later that she shaved it because it was more comfortable. He reached up to run his fingers down from her breast to her thigh, and he started to stand up as well, but Mabel put her hand on his shoulder to keep him seated. Then she turned around, showing him her firm butt, and slowly sat down on Dipper’s right thigh, pressing her back to his chest, and straddling her feet to either side of his leg. Dipper’s right arm wrapped naturally around her waist, his hand perfectly falling between Mabel’s legs. His other hand reached up to cup her left breast. Mabel tilted her head down to reach Dipper’s mouth, and planted a quick, hard kiss as she pulled his hand to her aching vagina.
Dipper was being given an anatomy lesson by touch alone: he couldn’t see where his fingers were being led. But he was a good student, as he allowed Mabel to guide his fingers to her sensitive spots. His fingers were traced up and down her labia lips, tickling just so. His middle finger was introduced to the inside of her vagina, and it was taught how to stroke the front wall of the tunnel with just the right pressure. She demonstrated how to move her vaginal fluids around to keep everything slick and lubricated. Finally she pressed his fingertip to her clitoris, and showed him how to rub the button to bring her the greatest pleasure. The lesson had no words: Dipper needed only to listen to her noises and feel the reactions in her body as he held her. Quickly he began probing Mabel on his own, and she leaned back against Dipper to slowly drown in the sensations that were building in intensity within her.
As he became more comfortable with what was working for Mabel with his right hand, Dipper started giving more focus to his left. His hand moved over Mabel’s breasts, first one then the other, squeezing and pinching one moment, then light caresses the next. He learned quickly from her reactions what worked and what didn’t, and soon got into a rhythm with both hands that he could feel was building Mabel’s passions with greater and greater urgency.
Mabel was lost, completely at Dipper’s mercy. He couldn’t know how well he was playing her young body, like a fine instrument. Her body and voice reacted to her rapidly growing arousal, and her brain was barely along for the ride.
Just as Dipper was sensing that Mabel was approaching her climax, an idea came to him and he acted before he had time to reconsider it. While keeping up his rubbing of her clitoris with one hand, he grasped Mabel’s left breast in the other, turning the nipple toward him. He arched his neck and sucked the breast hungrily into his mouth, then he quickly reached across her body and used both arms to hug her tightly into himself.
The shock of feeling her brother’s lips and tongue against her nipple, accompanying the magic his fingers were working between her legs, was more than enough to trip Mabel into a thunderous orgasm. Her gasps and groans became a wail that only hinted at the level of pleasure she was feeling. Again and again his fingers and mouth brought her back over the edge. Finally, she had to helplessly flail to Dipper that she needed him to stop. She felt she would die if he didn’t stop. When he finally did, her body lost all its strength, and she sagged forward while she desperately gasped and heaved lungfuls of air.
Mabel’s shifting weight caught Dipper unprepared, and he had to scoot down on the bed to balance her. That put him far enough over the end of the mattress that he could feel himself starting to slide off. He was going to tip forward and drop her on the floor in a moment, and then he was going to sprawl on top of her! Saving her the only way he could, Dipper pulled both his hands free, quickly slid them under her butt, twisted himself out of the way, then unceremoniously heaved her backward up onto the bed just before he landed on the floor with a thud.
Laughter was added to the mix of gasps in Mabel’s breathing. She was splayed out on the bed on top of the haphazardly strewn bathrobes, knees bent, one foot hanging over the edge to the floor. Through her hacking, laughing coughs and deep breathing, she blinked helplessly straight up to the ceiling but managed to ask Dipper if he was okay.
He was more than okay. As soon as he landed on the floor, Dipper had immediately got to his knees and turned to check on Mabel. Directly in front of his face, not a foot away, he gazed upon Mabel’s nether regions, as if she was offering herself for examination. He was fascinated, seeing what he had only felt before. All the folds, flesh of different shades and textures: even the aroma was intriguing to him.
Dipper’s libido was back in force. Mabel’s incredible orgasmic reaction had stirred desires in him that he had never felt this strongly. In another spur-of-the-moment decision, he acted on something he had only seen done in that one brief exposure to a porno video. Giving Mabel not nearly enough time recover from her previous climax, he dove his mouth into her vulva, while wrapping his arms securely around her thighs, pinning her down. With one long, single stroke, Dipper’s ran the tip of his tongue firmly from the opening of her vagina up to her clitoris, pausing there long enough to rub it up and down.
Mabel went from moan to full-on scream in under five seconds. It was a sound indistinguishable from one of terror. Dipper would have thought for sure that he was hurting his sister. But two things told him otherwise: Mabel’s hands had secured to his hair and she was pulling him hard into her crotch, and her legs were holding his head in a death grip. Dipper hoped like heck that security didn’t come pounding on the door. He couldn’t see or even move his head, so he just blocked out the pain from the roots of his hair and started flicking his tongue again, while quickly sliding his hands up her body to find Mabel’s nipples and give them a pinch each.
Another orgasm smashed down on Mabel, hard on the heels of the first caused by Dipper’s tongue. She had just been arching her back and stretching her head back through the first one. She let out a strangled screech, and convulsed forward to nearly a fetal position as she rode through the frenzy of her come.
After what seemed an eternity, she came close to passing out from simple lack of oxygen. Her quick gasps were not keeping up with the needs of her body in such an excited state. The only thing that prevented it was that Dipper had also run out of breath, but he was literally unable to get his face free. Having to abandon pleasing Mabel, he had to struggle to pull his head back, and grabbed Mabel’s hands to force her fingers out of his hair. They both collapsed beside one another on the bed to catch their breath.
“Oh my … God, Dipper!” Mabel panted. “I … love you … so much!” as she reached a hand out to her brother.
Dipper took her hand and panted back “I love you too!” then crawled across the bed to snuggle up to his twin. He held her close, stroking his hands all over her body and kissing every patch of skin he could reach between gasps of air. His leg rubbed up and down on hers. He was very fired up now, and very aware of his now-hard penis pushing against Mabel’s hip.
She could feel it too, and decided that now was the time. He had been gloriously wonderful to her, and knew the night could not be complete unless they completed each other. She was absolutely determined that she wanted him inside her now!
- 6
- 7
- 8
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Fistbump (a Pinecest story)