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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.

Chapter List
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4 Soft and Hard
Mabel gazed into her brother’s eyes as she pumped his dick between her tits. Licking her lips and cooing, she murmured, “Is that nice? Do you like that, hmm?”
Dipper thought, My God, she’s so hot right now! And he’d often fantasized about getting a titty fuck from a certain redhead. And Mabel wasn’t Wendy, but this felt good. He groaned and said, “Yeah, I think I can cum again.” He was barely perched on the edge of his bed, leaning back, hands braced on the mattress.
Leaning toward him, Mabel tilted her head and every time she bobbed low, she let the head of his cock rub against her cheek and across her face, under her nose. She took a long sniff. “You smell nice,” Mabel said. “Let me see if I can—” she knee-walked the pillow a little further from the bed and adjusted her position. “Oh, yeah.”
Dipper shivered as she bent her head forward and gave the tip of his dick a wet, hot, loving lick. “Whoa!”
She smacked her lips. “Mm, tasty pre-cum! Hee, your face looks like Tomato Dipper. Tomipper! Don’t freak out on me, Brobro. Uh, I know we’re taking this a step at a time, but if it’s okay with you, I’d really like to suck you.”
He felt his heart pounding and his dick throbbing. “Uh—”
“Just a little bit. It’s way past lunch time, too early for dinner, and I just wanna see what it’s like,” she coaxed in her most appealing voice. “I promise it won't make me barf, so relax. Come on, I’d let you do me if you wanted to.”
“Mabel, we’re going too fast. I mean, what you’re doing now, I like that. A lot. You’re so soft and—"
“Yeah, but it’s doing more for you than me. It’s nice, but I really want to suck on it for a few seconds. Just let me try it for size. Please?” She tilted her head like a puppy expecting a treat.
Involuntarily Dipper’s dick got even harder and a tiny bit longer. He caught his breath. When he failed to speak, Mabel didn’t wait for permission. Gazing down on her, he saw the ripe double swelling of her buttocks and realized she had her left hand down there, frigging herself. Her now abundant, jiggly boobs held his dick captive with the help of her right hand clamping over them. He felt her lips open and shivered all over as she took the head of his cock into her mouth.
Dipper moaned a little. “Maybe that’s enough. I don’t think we should—"
Ignoring him, Mabel started to polish the taut purple helmet with her tongue. Then she moved her head backward to study his expression. He could see her tits more clearly, the nipples darker and jutting with excitement. She almost took her mouth completely off him—almost.
Instead, she kept her lower lip beneath the coronal ridge at the base of his glans and her upper lip just covering the slit. Impishly, she sucked and then popped her mouth, making his penis bob. “Yum!” Mabel licked her lips as she grasped his dick with her right hand, letting her tits bob free, while she rubbed herself off with her left. “I can do it! I want to do it! I really, really want to suck you off, Brobro,” she said huskily. “I mean I want you to shoot your cum into my mouth.”
He didn’t trust himself to speak but, carried away with the moment and tense with anticipation, he nodded. She was still slowly sucking him. She interrupted to look up again. Not breaking her gaze, she calmly said, “Now, in the movies the girls like jerk the guy off with their hand while they suck the knob. Is that the right way?”
How am I supposed to know? No girl has ever gone this far with me! But I’ve seen it in videos, too, Dipper thought. Aloud, he croaked, “Try it.”
“Mm!” She took his dick head in her mouth and sucked and began to bob her head, not taking in much more than just his engorged glans and maybe the upper inch of his shaft. Tantalizingly, she changed the rhythm of her hand, bringing her grip up while her mouth was going down and then vice-versa. And her tongue was really working overtime.
So hot, so slippery, so soft and always in motion! Mabel slurped audibly. “I’m close!” Dipper warned.
She didn’t answer but sucked and bobbed with increased enthusiasm. Now he could even hear the slushy sound of her fingers moving in and out of her own pussy. She had to be super wet, right on the edge herself—
“Hhah!” Dipper gasped as his whole body tingled and spasmed. Mabel sucked ferociously. And then his throbbing dick pumped a gush of cum right into her mouth. She didn’t stop bobbing until his orgasm had faded.
She leaned back on both hands as his subsiding penis drooled a drippy, bubbled, pearly string onto her right boob. His sister wore the most enthusiastic smile, and both her cheeks bulged. “Ook ere!” She opened her mouth and with her chin tilted up, thrust her tongue forward, tip curled. Creamy cum coated it and flowed toward the back of her mouth.
She closed her lips, closed her eyes, and blissfully gulped. She licked her lips before bending and lapping the head of his cock again. Then she cuddled his dick against her cheek, tenderly pressing his cock head to her flesh and leaving a faint wet trail across her face. With a happy sigh, she said, “You liked that!”
No use fibbing or even understating. She'd been there, she knew how he'd looked and acted. “It was great,” Dipper said.
Her fingers were still working on her pussy, schuck-scluck. She wriggled her hips. “Unnh! So you want to help a sister out? I didn’t cum! I sucked you off and swallowed, and I was concentrating on you, so I’m nearly there but now I don’t know if I can do it on my own. So how about going down on me, Mabel?”
Dipper was sweating. “Mabel, I—”
“Aw,” she said pouting at his facial expression and the tone of his voice. “After I was so nice to you. Okay, I get the message. I'm just undesirable.” She sniffled.
“No, no,” he said. “I—I’ll do it. I’ve never done it, and I may be terrible at it, but—”
“I’ll coach you,” she said, getting up off her knees and leaning to hug his head, her boobs cushioning his cheeks.
When she gave him air, he said, “Uh. All right. How do we—”
“Give me a second. Heh! Then give me a licking!” She got into bed and lay back—properly, head at the head, back propped against the wall—and spread her legs, revealing the pink gleaming flower of her pussy. She whispered, “I’m so close, Dip. Get down there and put your fingers deep in me and then lick my slit and suck my clitty.”
He couldn’t help staring at her shiny, flowing opening. “I may do it wrong—”
She pinched her right nipple, wiped up the drip of cum that had fallen in an arc on her boob, and sucked her finger. “Go, go, please go ahead and do it before I cool off!”
Dipper lay on his stomach, a little awkwardly because his shins stuck over the foot of the bed, so Mabel moved back as much as she could abd ket gun lie more comfortably. As soon as he adjusted his position, she put her thighs on his shoulders and raised her butt. “Here you go,” she said. “Open for eating!”
Dipper leaned down, slipped first one and then two fingers inside her hot, wet slit, and started to move them in and out. She was right, she had made herself more than welcoming, and his fingers slid in with no resistance other than a friendly, accepting squeeze. Now his face was so close to her pussy that he could feel its heat, radiating, carrying with it her musky aroma. Her fragrance was intoxicating.
He found a rhythm with his fingers. “Is this—”
“Yeahhhh,” Mabel all but purred. “Finger-fucking is great! My clitty would like some tongue now, please!”
With his face feeling as if it were on fire, Dipper got his mouth into position and stuck out his tongue, dipping it into the top part of her slit. To his surprise, the taste really was pleasant. Not exactly salty, not exactly sweet, a tad on the acid side. Mabel moaned as he started to lick and continued to thrust his fingers into her depths.
As he swept his tongue up and down, she squirmed and pushed her pussy against his mouth. “Lick harder with your tongue,” she said. “Find the little button at the top, that’s my clitty. Let me—open up for you a little more—” she moved her thighs so that her ankles crossed against his upper back and her thighs were on either side of his cheeks. His tongue probed.
She writhed. “Aw, yeahhh, right there. Yes! Now polish my clit, please. Yeah, little lower—there! That’s it. It feels round, I bet. Aw, yeah, sooo good! Now flick it with your tongue tip, Dip! Pump me with your fingers! Make me cum! Faster!”
Dipper had rotated his hand so his palm was under his chin. He crooked his forefinger and pressed the inner surface of her pussy but kept moving both hand and tongue. Now her clit had definitely swollen, and he felt its yielding, pliant nub as Mabel started to quiver all over. That spurred him to lick even faster and press harder.
Mabel grabbed his hair with both hands and suddenly squeezed her damp, supple thighs, clamping his ears, as she yelled, “Oh, my freakin’ GAWD! Ohhh, yeah!”
This time when she came with a shudder, she didn’t squirt very much, but Dipper tasted her sexual nectar, and when she relaxed, gasping, he pushed up on his elbows. She looked down over the mounds of her breasts and gave him a thumbs-up as she crossed her ankles again and leg-locked him for a special hug. “You—you did good!” she panted. Then she giggled. “Your face is all shiny from your upper lip down!” She uncrossed her legs. “Get your butt up here and cuddle me, Brobro!”
He spooned her, her butt crack like a bun, his now-flaccid penis like a happy hot dog. “I really think we better stop here,” Dipper said, nuzzling her neck. “For today.”
In a pouty voice, Mabel said, “Aw, man! Just when we were getting good! Are you sore?”
“Little bit,” he said.
She turned her head, trying to look over her shoulder. “Your poor dick hurts?”
“A little,” he confessed. “I don’t remember when I ever jerked off more than three times in one day, so it’s kind of tender now. Also, my tongue. I think I must have scraped it a on my bottom teeth.”
She flexed her buttocks, giving his cock a friendly squeeze. “Sorry, Broseph. I know I get carried away, but I gotta say, Wendy’s gonna love this kind of playing around! She may teach you some brand-new tricks. She’s more mature than you, she’s had a lot of boyfriends—don’t get jealous, ‘cause I know she thinks you’re the one, but it’s true. So if she’s got any tips, make sure you tell me about them. Pass it on, Bro, pass it on.”
After a minute or two, she took hold of Dipper’s hand and moved it to her boob. “These feel so much more sensitive now,” she murmured. “Do you like them? Do they look good on me?”
“They look fantastic,” Dipper said.
“Do they feel good?”
“Mm-hmm. Nice and squeezable. And I like the way your nipples stick way out.”
“Um, how did I taste?”
“Your nipples? Good. And so stretchy—”
“I meant how do I taste down there, Dipdop!”
Dipper chuckled. “Really nice,” he said. “I’ve been trying to think of what it reminds me of.”
“Not fish!” she said. She covered her face with both hands. “Oh, God, don’t tell me I taste like tuna!”
“No,” he said. He screwed up his face in thought. “Um—more like, uh—you know that time when we tried mango juice? Like that, but sort of as if you watered it down and maybe put a tiny sprinkle of salt in. Not at all sharp, and not exactly sweet, but nice and tangy, I’d say.”
Mabel writhed and turned until she lay hugging him, her boobs pressing into his chest. “I’m so glad! And you taste good. Your cum is sort of salty, but—it’s hard to describe tastes and smells, isn’t it? Um. When I was holding your cum on my tongue, it was just a little bit—peppery? I mean, not like a jalapeño or anything, just a hint of spice, but I loved it!” She yawned. “And now I’m hungry. It’s getting pretty late.”
They put on clothes to go down to the dining room and eat, though Mabel went without her bra, instead pulling one of Dipper’s tee shirts down. She did consent to wear her panties, though. Dipper wore his jeans and another tee, this one a souvenir from Gravity Falls with the Mystery Shack logo on it.
They kept giving each other embarrassed smiles, and Mabel couldn’t help giggling now and then. They drank sodas—lemon-lime, no caffeine after noon—and fed each other, scooping chicken salad and hummus on the celery ribs. “Open wide. There you go!”
Dipper held up a grape, and Mabel took it, and his fingers, into her mouth and lasciviously sucked until it popped inside. “I love the juicy ones,” she confided. She mildly complained about the sodas. “I wish we could buy Pitt Colas here. I would kill for one right now.”
“Don’t think it’s legal to sell them outside of Oregon,” Dipper said.
Mabel swigged her lemon-lime and made a face. “First thing I do when we get to the Shack is drink a Pitt. Hey, Dip, you know how in the romance stories the guys drink champagne from a lady’s slipper?”
“No,” he said. “First, I don’t read them, and second, your shoe would be all nasty and sticky and you’d never get it clean.”
“Not my idea,” she said mischievously. “See, what I’d really like to do, I mean before Wendy comes back to the Falls and I gotta give you to her, I’ll get a Pitt, not too cold, and I’ll lay back in bed naked with my butt way up and you can pour the soda into my pink wine cup and slurp it out—”
“Let’s . . . put that in the maybe file,” he said.
“And I could pour some over your dick—the bubbles would feel all tingly—and I could go down on you—”
“Maybe file,” Dipper repeated firmly.
“Yeah, but we’d have to put like a million towels on the bed first. Or a plastic sheet! That would—”
“Maybe. File.” That finally ended the speculation.
At his insistence, and with her mild objections, they washed and dried the few dishes they had used and dumped the grape stems and small blobs of hummus and chicken salad into the disposal. Out of the blue, Mabel said, "Think if you zapped my clit with the grow light it would make me cum harder?"
"Probably," Dipper said. "After I did my dick, I started to squirt harder."
"To the bedroom!"
As he was carefully, carefully giving her clitoris a bit more size, the house phone rang. It was their mom, and Dipper spoke with her for a few minutes. “Dad’s still doing good,” he told Mabel after the conversation ended. “He has to do these breathing exercises every two hours, but he can get up on his own and walk to the bathroom and everything. Mom put him on the phone, and he said to tell you he loves you and he’ll have a long face-time with you tomorrow evening when he’s home and we’re in the Shack.”
“Aw, you should’ve put me on.”
“Sorry, he was tired. But he’s turned the corner, anyway.”
“That's good to hear. Now I'm kind of bored. Want to play?” Mabel asked.
“Sure!” Dipper said. “Let’s go to the living room!”
He broke out the video game, Lazer Razer Racers.
“Aw, man!” Mabel said. Dipper sat on the sofa and patted the cushion next to him. She grabbed the controller and pouted, “This is NOT the joystick I wanted in my hand!”
They played the game for a while. Dipper was all about finesse and control. Mabel, on the other hand, loved to make ridiculous jumps from freeway bridges, deliberately aim for pedestrians or city buses, and in general play as if she were a maniac. “Hey, a hundred points for me!” she said after taking out ten hapless bicyclists who were doing a rally in the bike lane.
“Do me a favor,” Dipper said. “If gruncle Stan lets us drive tomorrow, turn him down.”
“No way! Look out possum! Mabel’s comin’ atcha!”
Dipper won three races in a row, and the afternoon wore away. Mabel had opened a package of chocolate wafers and had been more concentrated on munching those than racing, anyway.
When she finished the last cookie, she rose, dropped the controller, and stretched, facing Dipper and grinning as she raised her arms way over her head, tightening the tee shirt over her newly big boobs and pulling the hem up to reveal her tiny pink bikini undies. “I want to take a bath,” she said.
“We showered already. Anyway, you’ve been eating. Don’t go in the water for an hour,” Dipper warned her, mimicking their mom.
She laughed. “I thought you said that was just a superstition!”
“It is, but it’s about swimming. Take your bath. I’ll put away the game and then I’m going to read for a while.”
“No more sex?”
“Please, not today. I don’t want to go up and see Wendy with a broken dick—hey!”
She had laughed, spraying him with chocolate crumbs. “Sorry, sorry, here, I’ll get that.”
She ran to the kitchen, came back, and lovingly wiped his face with a napkin. Then she put her hands on his cheeks and tilted his head back, her brown eyes wide and her gaze fixed on his. She smiled. “Thanks, Dipper,” she said. “In a purely sisterly way, I love you. And I also mean that in a sexy way!”
He was still on the sofa, and she sat in his lap. “It’s . . . I’m still uneasy about this whole idea,” he said. “I can’t help that. Still, you’re a really stimulating girl. And you can talk me into anything.”
“Into ANYthing?” she asked.
“Um, not into putting my penis in your pussy,” he said.
“Oh, pooh!”
Mabel went up to their bathroom. Dipper went to his room and found the book he was reading—nothing for school, a collection of anecdotes about ghosts and hauntings. Just as he started to lie down, Mabel called him from the bathroom.
He found her sitting in the half-filled tub. “Help me out?” she asked.
“How?” he asked, looking down on her lush body. She had tied her hair back, making herself look a little more mature.
She waved an arm, making her boobs bounce. “I forgot to get the bubble bath from the cabinet. It’s the new bottle on the top shelf. The bottle with the pink label, Babylon Bubbly.”
Dipper found it. “Here you go.”
“No, don’t hand it to me! Squirt it under the faucet!”
Dipper flipped back the cover, tilted the bottle, and squeezed. A jet of thick white bubble bath shot out, and bubbles started to form.
“Hey, Dip!” Mabel said. “Gimme a shot on these babies!” She cupped her shiny wet boobs, and, grinning, he scored a direct, splattery hit. The pearly-white liquid pooled and dripped.
“Happy now?” he asked.
She looked down, admiring the squiggles and drippy splotches of white. “Remind you of anything?”
“it smells a little like coconut and brown sugar,” he said.
“You’ve got no sense of fun!” Mabel swept bathwater onto her tits, dissolving the liquid into foam. “Mm, so slippery. Go and read your stupid old book and see if I care.”
“Okay. I’ll bring you a towel, first.”
“I always forget,” she said. “Turn off the water, too, cold tap first.”
“This,” Dipper said, “must be the way Pacifica treats her boyfriends!”
“Ew!” Mabel replied.
“Anything else?” Dipper asked when he had put the towel down on the small tub-side table.
“No, I’m good. This feels so relaxing. I’m gonna just lie here and soak until the water cools and think up more ways we can have fun. Maybe take my new and improved clitty for a test drive”
“Fine, I’m going to get my book.”
“Go on, brobro,” she said cheerfully from her nest of aromatic bubbles. “I know where to find you.”
***
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Helping Hand