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Helping Hand	By : Nastyzak Category: +G through L > Gravity Falls Views: 4143 -:- Recommendations : 0 -:- Currently Reading : 1
Disclaimer: I don't own Gravity Falls or the characters from it, and I make no money from writing these stories.

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2 High Jacking
As she fondled and caressed Dipper’s erect shaft, Mabel said, “This is so cool! I wanna get in close so I can see everything.” She reversed in the bed, her feet on the pillow, and urged Dipper, “Scoot down. Come on, bend your knees if you have to. That’s good! Now I can see what’s going on.”
Her head was now level with his belly button, and she lay on her left side. She propped her cheek on her left hand and masturbated her brother with her right. Dipper groaned as she picked up the pace.
She stopped to ask, “Oops! Does that hurt?”
“No,” he said. “But maybe . . . not so fast, okay? I don’t want to cum so quick. It’s always a problem for the girl if the guy, you know, quits too soon.”
She slowed down and kept her eyes on the dick she was pleasing. “Something clear is coming out of your pee slit. It doesn’t look like the white goop in the videos when a guy shoots on a girl’s boobs or face. What’s the watery-looking stuff that feels so slippery?”
“That’s called pre-ejaculate. Most guys call it pre-cum. It lubes everything up.”
Mabel’s eyebrows rose. “Oh. Makes slipping into a pussy easier? That must be why girls get wet. I’m starting to feel sort of damp down there, too. Do you mind me looking at you so close and personal? I’ve never seen a real one, and when you freeze a video, they’re just a blur.”
“I don’t mind,” he said. “Maybe talking will keep me going for longer. Is my—is it ugly?”
“Huh? No. I think it’s pretty. And I like how tight and shiny and purple the knob on the end is. What’s that called?”
“That’s the glans. It’s sensitive, especially that ridge at the base.”
“The thing that makes it look like a tempting mushroom? Does that have a name?” She traced half of it with her finger, gliding along on the slippery pre-cum.
“Yeah. C-coronal ridge. That’s extra sensitive. Careful!”
“Coronal ridge. Glans,” she repeated. She squirmed even closer so her boobs pressed against him, feeling hot. “Your glans looks so swollen. Is it like, you know, my clitty? Because mine swells up when I’m feeling sexy.”
“Y-yeah,” Dipper gasped. “Just like that. Both my glans and your clitoris have lots of nerves in them to make them sensitive to pressure. Ahh! That’s a good rhythm. You can go a little faster now.”
“Okay.” She changed the beat, so to speak. “Would it help if I put lotion or cream on your dick before I did this? In a lot of the videos, they pour some kind of oil on each other. Baby oil or something.”
“You could, but I don’t really—unh!—need it. Never even tried it. Guys who have foreskins need it more than ones like me. Circumcised.”
“Is that like super-sized, or—”
“Please!” Maybe the chattering was a mistake. Dipper had lost a little headway. “You must know—you don’t? Okay, let me explain. When guys are born, they have skin loosely covering the whole head of the penis, the glans, even the tip."
"Then how do you pee?"
"There's an opening in the skin, and it kind of slides around. I guess guys with foreskins sort of pull them back a little to pee. I don't know for sure. When I was a newborn baby, mom and dad had the doctor take off that end flap of skin. All Jewish guys get it done, either by a doctor or by a mohel, a rabbi, if the family's really religious. One way or another, the floppy, loose foreskin is cut off. That’s what circumcision is.”
“Oh! Ouchy! Sorry.”
“I never knew what it was like to have a foreskin, so I don’t miss it.”
“Do you mind if I spit on your dick a little? The leaking’s nearly stopped, and I’m afraid the friction will hurt you—”
“If you want to do it,” Dipper said.
Mabel moved until her mouth was right over the tip of his penis. Then she flicked it with her tongue. “Little salty, but not bad! Here you go.” She drooled a little, her hot saliva feeling unexpectedly exciting, and his dick suddenly felt very, very good. He arched his back.
“Whoo, you just popped up about another half inch! Are you close?” Mabel asked.
“Uh-huh!”
“Little faster now?”
“Yeah—”
“You’re moving your hips. Oh, I like the texture of your dick! Faster now.”
She sped up, her face only inches from his dick, so close that he could feel her breath whenever she exhaled. He felt the tension grow to bursting, and then with a spasm and a jerk, he shot his load, hard.
Mabel moved back a little and said, “Wah-wah-wowie! It nearly hit the ceiling! Now it’s splattered on your tummy and running over my hand. Did you really cum?”
A panting Dipper gave her a look. “Cumming is when that happens with a guy, uh, when the semen shoots out. And I really did cum. What are you doing—oh.”
Mabel was sucking on her fingers. She swished his cum around in her mouth and then swallowed. “Not the tastiest thing I’ve ever tried, but far from the worst. I even like it! What’s wrong, broseph?”
“Nothing, but you swallowed my sperm.”
“Oh, was that bad? The Video Slutz always gulp it down. Did I do wrong? Should a girl not swallow a guy’s cum?”
Dipper grimaced. “It feels so wrong talking about this stuff with you! But if you really want to know, I think most guys are, uh, flattered if their girl likes their cum enough to swallow and not spit it out.”
Mabel grinned. “Oh, yeah, in the videos the sluts open their mouth to show it pooled up on their tongue and hanging stringy from their lips, and then they swallow. I’m sorry I forgot that showing-you part! Aw, look, you’re all droopy.”
“You don’t have to show the guy the cum in your mouth,” Dipper told her. “I can’t believe I just said that!”
“Here—let me—”
She leaned down, he felt her breath on his cock, and then she licked up the stray runlets of jism. “I can’t get hard again so quick,” he pleaded.
She smacked her lips. “Just tasting. How much of a dick does a girl have to take in her mouth to make a guy happy?”
“I don’t know,” he confessed. “No girl's ever gone down on me. But I don’t think it’s necessary to deep-throat a guy.”
“What in the what now?”
“To let a guy stick his dick all the way into your mouth and into your throat, so your nose is bumping against his pubic bone,” Dipper said. “From the videos I watch, it makes it hard for the girl to breathe, and their eyes water and their noses run. Guys in the locker room have boasted that they made girls gag and puke by sticking their penises too far in their mouths. Sis, don’t do anything that hurts you or makes you uncomfortable. That tickles!”
She was licking the cum off his abdomen, and she paused to pluck a stray hair from her lips. Then, in a small voice, she asked, “Uh, Dipper?”
“What?”
“Um, doing all this got my motor running. Would you help me out a little? Please?”
“How?” he asked suspiciously.
“The way I helped you.” She raised her right thigh. “Rub me down here? You know, give me a, uh, a finger job? Is that what it’s called? Or just fingering? Either way, would you please pet my pussy, hmm?”
“I . . . really don’t know how,” he said, honestly. He’d never done it, and in the videos he’d snuck to see on his phone, the guys rammed their cocks straight into mouth or pussy. “I might hurt you.”
“No, just be gentle. I’ll guide you.” She lay mostly on her hip and really opened her legs, giving him a spectacular view. “Okay, first reach over and just sort of cup your hand around my pussy. Yeah, like that. Your hand is so warm! Can you feel how wet I am?”
“Sort of.” It was true, the pouched lips of her pussy felt definitely damp against his palm.
“Now listen. Keep your hand there where it is. Now crook in your middle finger. Yeah, I can feel it. Now use it find my slit. Don’t try to poke! Wait, wait, let me tell you. What I want you to do is to move your hand off me just a little so the tip of your finger can curl and go up and down my slit. No, start a little further from my clitty. There you go. Now move it back and forth, just inside the slit. Mmm, You’re doing good. And look, your peeny is twitching again!”
Dipper marveled at the silky smoothness of Mabel’s sexual crease. When she breathlessly said, “Now give me more,” he pushed the tip of his finger a little deeper. She generously flowed with slippery juice. She was gently masturbating him again, lazily, almost casually, slowly arousing him. She started to squirm and thrust with her hips.
“This is doing it for me. Mmm, yeah! Oh, Dipper, I can’t help moving like this! Now you can put your finger in deeper. Wait, wait—now. Push! Oh, yeah!”
His head spun with excitement. Dipper thought, I’m finger-fucking a girl, and she loves it! But it’s Mabel! I’m going to hell!
Her pussy almost sucked at his finger. She hummed and moaned and jacked him off harder. “This is so good!’ she said. “My nipples feel like bullets! Oh, my God, I think I’m gonna have an orgasm!”
“I’m close, too!”
She moved again. She was panting, and her voice became husky. “Now find my clitty, up at the top of my slit—no, the top, the top, other end! Yeah, right—right there, that’s it—move back—right there, right there! Feel that little button?”
“I feel it.”
“Real fast, flick your fingertip over it! Faster, you won’t hurt me. Ahh-YI!”
A tiny gush of hot liquid spurted over Dipper’s hand. It startled him—but also triggered his second cumming.
This time Mabel put her face over his dick, so the white streamers jetted right into it. She gasped and then pulled away, swiveled, and flopped down with her head level with his. She took three deep breaths. “Dipper, that was the best I ever felt in my whole entire life! I don’t think I ever came before that. I thought I had with Mr. Buzzy, but that, whoa, my God, it feels so great! How do I look?”
He reached to touch her face. “Like you’ve been frosted,” he said. She had one long, thick drooping strand of cum right across her chin, up her cheek, onto her forehead, and random splatters on her nose and cheeks and drops in her dark hair. He wiped the cum with his fingers and before he knew what she was doing, she grabbed his hand and sucked his fingers.
“That’s pretty kinky,” he told her as she writhed her tongue over his fingers and then his palm.
She giggled.
“Uh, Mabel, right there at the end—did you pee?”
“No, I think I cummed!” she said. “Came? What is it? Doesn’t matter, I squirted! I’ve seen videos of girls squirting! Lots of times when they were getting each other off with vibrators! I never did it with Mr. Buzzy, but now I did it with you!” She fell silent for a moment. “It, uh, didn’t feel like peeing. Uh, does that turn you off?”
“No,” Dipper said. “Where did you find those kinds of videos?”
“Online, Brobro,” she said. “On my laptop, in my bedroom. Don’t you watch ‘em too?”
“Just on my phone because the adult sites are blocked on the Wi-Fi. How did you manage—”
“I’ll show you how to turn off the kid filter,” she said, stretching languorously. “Um—I feel so kind of drifty and nice—kiss me, Dip?”
He turned on his side to kiss her cheek, but she gave him a wet one right on the mouth. Her tongue forced his lips apart.
He sighed and rode with it, tasting her tongue and probably his own cum. He didn’t know what it was supposed to taste like but there was a definite hint of salt there. Mabel reached down to her crotch and then said, “Suck my fingers, Dip.”
Her index and middle fingers gleamed with Mabel juice. Oh well, what the hell. He did.
“Do you like the way I taste?” she asked impishly.
“It’s . . . um, tangy,” he said. He licked his lips thoughtfully. “Not bad.”
“Okay, so when we rest up, we’re gonna do mouth stuff to each other, all right?”
“Uh, Mabel—we’ve been, you know, just fooling around. Oral sex is, um, real sex. I’m still not sure I’m okay with all this. I think we’re going a little too fast.”
“Oh, poo! Oral sex is NOT real sex. Real sex starts with an F!”
“It seems wrong,” Dipper said.
Mabel grimaced. “Well, if not that—I’m gonna get Mr. Buzzy. And you can get down on your knees and I’ll lay across the bed and open up for you, and you can watch it in action. It’s pretty much like your dick, but not so long and thick. How’d you get such a big dick, anyway?” She reached down and idly caressed it.
“I don’t know,” he fibbed. “Born with it, I suppose. You know, genes and all that. Um, you’ve still got some blobs there and there—"
Mabel wiped cum from her forehead and chin and then licked up the jizz. “This isn’t as good when it cools. Note to self: Drink only fresh, hot cum.” She guided Dipper’s hand to her boob. “Guess we should have started here, huh? With some first-base kind of making out? I did move fast. Go ahead, feel it up. Do you like my boob? How is it?”
“Nice and soft, Mabel. Except for the nipple.”
“Yeah, they always stick out like that. It’s okay, rub that one hard. Pinch it. Oh, harder than that! Stretch it. If you start with Wendy’s boobs, remember, don’t’ just grab her nips straight off. Stroke her whole soft booby. Then go in with your mouth. Nuzzle and nibble, then when her nippies start to get erect and throbbing, you can get rougher. Don’t bite them, though. At least, not hard.” She sighed. “I wish my boobs were bigger!”
“They’re fine,” Dipper said. “A good mouthful is all you need.”
She punched his shoulder, not hard. “I don’t want a rack like a porn star’s, but a little more up top wouldn’t hurt. Why don’t my genes work for me? It’s like—” she broke off. Then, suspiciously, she asked, “Dipper, tell me the truth. Did you use the grow and shrink flashlight on your peeny?”
“Don’t call it that,” he said. “Penis or dick or cock or anything but peeny!”
“Seriously, did you?” she asked.
Dipper thought fast. “Don’t you think you would have found it if I’d brought it home?”
She settled back, and he took his hand off her boob. She caressed her own breasts, kneading them and pulling on her nipples, as she muttered, “Yeah, I’ve tossed your room often enough. That’s a cop term. Means I’ve searched—”
“I know what it means, Sis.”
Mabel was silent. Dipper got up the nerve to roll her onto her back and then move down. “Whaaat are you doing, Brobro?”
“What you suggested.” He moved her hands and nuzzled her boobs. They had a distinctive, extremely exciting aroma. He pursed his lips to suckle her nipples. She put her hand in the back of his hair. “Feels nice, brobro. Suck that one in. Now polish it with your tongue. Nice! Remember when you’re kissing my clitty to—wait a minute!”
She pushed him away. “What?” he asked.
She crossed her arms over her chest and gave him an indignant glare. “I remember there’s a flashlight in the garage that’s exactly like the grow-and-shrink ray!”
“Lots of flashlights look like that! Anyway, we broke the crystal after Weirdmageddon, remember? You said you wished you could shrink all your friends and take them home in your pocket, and then you broke the flashlight and stomped on the crystal so you wouldn’t be tempted!”
“Oh, yeah,” she said, settling back. “Ugh, I’ve got sticky stuff in my hair. Want to take a shower?”
“You mean together?”
“Sure, what are you worried about? That I’ll see more of you than I already have?”
“I guess not,” Dipper said.
“Okay, let’s go to Mom and Dad’s bathroom. The shower stall there’s bigger than our tub.” She grabbed his hand and leaned back, tugging. “Get out of bed, Dipper! Come on, we’ve got until at least seven tonight, but let’s get a move on and use the time! You can scrub my back!”
Showering with a partner, even if the partner was Mabel, turned out to be very pleasant. As he palmed suds over her shoulders, back, and—frankly adorable—butt, she washed her hair, complaining, “It’ll take forever to dry.”
Then she washed his back for him. And pressed against him, her boobs softly flattening. And reached around. “Gotta make sure this little guy is clean if it’s going in my mouth. Um, not so little now! You’ve got stamina, Dipper, I’ll give you that—wait a minute!”
She forced him to turn around, facing her, at dick’s length. “I did break the flashlight and I stomped on the crystal! But Dipper—look me in the eye—did you sneak more of those crystals home with you?”
One drawback of having a twin is that you can’t effectively lie to them, not when gazing into their soft brown eyes. “I kinda did,” he admitted. “You got me.”
“Uh-huh! Rinse off and let’s have this out, brobro!”
They dried and went back, still naked, to his room, where they got under the sheet, the blanket tossed down to the floor. “All right,” he said. “Yeah, I brought home three of the crystals, and yes, I did rig another shrink-grow light with one of them. The flashlight I used is the one in the garage.”
“I thought so! And gave yourself a grade-A peen—uh, I mean dick, right?”
“I made it a little bigger,” he admitted. “Look, I always thought it was on the small side, so yeah, I gave myself a boost. But Mabel, it’s so difficult! I mean, the first time I tried, I misjudged the exposure and my dick got about three feet long and as thick as my leg! It flopped down and hit the floor, and it hurt!”
“So you shrank it—”
“And I was nervous and wound up with a little thing about as long as my pinky,” Dipper said miserably. "I finally bought an old camera, the film kind, in a junk shop. It didn't work, but I took it apart and got the iris out so I could focus the beam better. I didn't want to be stuck with a little, uh, you know . . .."
“Teeny weeny peeny!” Mabel said. She kissed the corner of his mouth. “Poor Dipper! So how much did you finally wind up adjusting it?”
“Well, before,” he said, “when I had an erection, it was about six inches.”
“About?” she asked. “You measured it, didn’t you? I bet guys measure them! You did, didn’t you? Huh?”
“Okay, okay, yes, it was five and a quarter inches. And the books say that isn’t bad, about average, but, you know, well, if I ever got a girl, I wanted to impress—”
“It’s bigger than any five inches now!” Mabel said. “How long?”
“Nine and a bit,” he said. “I tried it at a foot, and it was just . . . grotesque. Ten was still weird. Nine is as big as I can go so it looks like it should be on my body. Normally it’s nine max, but if I don’t masturbate for a few days and get real excited—”
“Looking at Wendy showing off her pussy,” Mabel suggested.
“Uh, yeah, like that, then it goes maybe a quarter of an inch longer. So nine and a quarter, tops. Uh, before I started sending photos to Wendy, I did juice it up a little so it’s always nine or around that now.”
“Nine should be plenty,” she said. “Now when you do my boobs—”
“What makes you think I still even have the crystals?”
“Bro, this is Mabel you’re talking to! Where’d you hide the crystals, anyway? I feel like I failed snoopology. Where’d you stash them?”
“On top of the ceiling tile in my closet,” he admitted. “It lifts up.”
“Good choice,” she said admiringly. “I never thought of that! Congrats!”
“Thank you,” he said.
Mabel nodded. “Okay. Good. So I’ve got a thirty-four-inch bust now. I think maybe thirty-six? We can try that and if it’s not big enough, maybe up to a thirty-eight? Or would that make me top-heavy?”
“Why not try thirty-six?” Dipper asked, giving in. “I think guys would be real interested in that. Now, if you also want really long nipples, I’ve worked out how to focus close with the camera iris.”
“Big, pretty, pink, sticky-outy nip-pips! Cool! We’ll try it,” Mabel said, pulling an imaginary whistle cord. “Toot-toot! Get on the boob train!”
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Helping Hand