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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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3 Sizing Them Up
Typically for him, by midmorning Dipper was feeling anxious. He asked Mabel to call Mom at the hospital because she’d be less short-tempered with her daughter than with her son.
“Hi, Mom,” Mabel said into the phone, unnecessarily adding, “This is me, Mabel, your daughter, calling you. How is Dad? Oh, that’s good. So are you planning to be back home at seven tonight, or . . . ? Really? Oh, don’t worry! We’ll be fine. Uh, yeah, I’ll get him here and put the phone on speaker. Just a second.” She held the phone a few inches from her face and yelled, “Hey Dipper! Come in here! Mom wants to talk to both of us.”
Dipper, sitting next to her on the bed, put his hands over his ears. He would have reached for the telephone, but Mabel held out a hand indicating “wait.” “He’s coming, Mom. I hear him on the steps. Of course we cleaned his room and changed the sheets! Mine, too. Here he is. I’m putting the phone on speaker now. Dipper, this is our mom. Say hi.”
Shooting her a glare, but keeping his voice pleasant, Dipper said, “Hi, Mom. How’s Dad today?”
“He’s been doing much better,” she said. “He’s had good bloodwork, and he’s going to spend one more night in the hospital and then tomorrow he’ll have some breathing exercises. Dr. Bronzowski says if he has a good night, he can leave the hospital sometime tomorrow, hopefully by noon or a little later. After I get him home, he’s to have quiet and bed rest for the next two weeks, and beginning on Monday a nurse will visit once every third day. I’m glad you kids called, because I’ve been too busy to call home and there’s been a change of plan for you two.”
“What is it?” Mabel asked. “Are we getting a pony?”
“We’re never getting a pony,” Mom said. “No, since we don’t know exactly when Dad will be released tomorrow, I’ve decided to stay with him tonight instead of coming home.”
“Is there room in one of those cranky beds?”
Mom sighed audibly. “They’ve moved in a cot for me. Dad’s doing a lot better, but he wants me to stay the night because he’ll sleep better, and he’s eager to get home as soon as possible. I’ve left everything for your lunches in the fridge—”
“You told me about it this morning before you left,” Dipper said. “What do we do tomorrow to get ready for Dad coming home?”
“Nothing, really. I’ve called the cleaning service. Gloria will come over around ten to clean and make sure the guest room is ready. She’s not going to make her normal visits for the next couple of weeks. Anyway, once Dad and I get home, I’m going to sleep in the guest room with dad, so he won’t have to deal with the stairs.”
With a wink at her brother, Mabel said, “And we’re under upstairs house arrest again. Blargh!”
Mom’s tone became slyly humorous. “No, I have a surprise. Your great-uncle Stanley is driving down from Oregon. He called an hour or two ago. He’s going to stay in the in a motel halfway there tonight, and then early tomorrow he’s picking you two up. You’re going back to Gravity Falls with him.”
“Mom,” Dipper said, secretly grinning at Mabel, “Are you sure? A long trip in this pandemic?”
“Gravity Falls has escaped the pandemic,” Mom said. “Not one case. Uncle Stanley told me, and I called the county health department up there just to make sure. It’s perfectly safe. You’ll have rooms in that tacky tourist attraction—it’s closed until the pandemic eases off. Now listen: You will be on your own up there, but your great-uncle lives only about a mile away and will check on you every day. He’ll see you have food and necessities.”
“A pony!”
“Not a pony. Never a pony. I’m talking about practical things, socks, toilet paper, soap, and so on. Mr. Ramirez and his wife are stuck indefinitely down in Mexico with his grandmother, sheltering in her cousin’s hacienda, until flying is safe again. I’d offered to send you up for two weeks, but Uncle Stanley has convinced me you might as well prepare to stay the whole summer. Take just what you need for a short stay, and we'll ship up the rest of your things after your dad's up and around again.”
“That’s cool! We really like Gravity Falls!” Mabel exclaimed.
“Some rules,” Mom said firmly. “First, call your dad at least three times every week. He’ll miss you and he’ll want you to talk to him. Face-time is best. At first, no conversation over twenty minutes because he gets tired easily. Later as he gets better, we’ll see.”
“Great!” Dipper said. “We’ll be sure to do that.”
Mom continued, “Second, if you don’t pass the distance-learning classes you’re taking with the college, you come home at the end of May, your summer visit will be canceled, and I’ll insist you take a full load of summer classes. You are not to have one long uninterrupted party! In fact, I want you each to take one or two online summer classes so you don’t fall behind. Be sure to follow your curriculum!”
Mabel made a face. “Mom? One course each, okay? They’re harder than you think. I’m not touching another math class so soon, but I could take Visual Design Theory 1 easy.”
“And I need a non-lab science, and I know the college is offering Astronomy,” Dipper added.
“Oh—very well, I suppose you do deserve at least that. Let me see, what was third? Oh yes, take care of Uncle Stanford’s house. Dipper, set a schedule. Dust and sweep twice a week. Clean up any messes you make. Do laundry. Keep the kitchen clean. Check expiration dates and toss old food from the pantry or fridge. You can have friends over, no more than two at any time. No sleepovers or wild all-night parties. Treat the house like it was you own.”
Mabel mouthed, “Opposite day!”
“Now,” Mom said, “you understand why you’re going, don’t you?”
“Yes, Mom,” Dipper said. “Dad needs to recuperate and recover, and you have to concentrate on helping him, and we should be safe up where there’s no germs.”
“That’s right. It’s not that we don’t love our children, but at the moment we just really need some time together so he can mend.”
“When will Gruncle Stan be here?” Mabel asked.
“He told me he’d be over early tomorrow morning, but you can call him after four o’clock today and find out details. I want you to phone me just before you leave the house and then when you arrive at Stanford’s house in Oregon.”
“Do we have to wait for Gloria to come and clean?” Dipper asked.
“No, she has a key, and she’s proved trustworthy.”
There was a little more fussiness from Mom, and then they all said, “Love you,” and the kids added, “Tell Dad we love him,” and finally they hung up.
“Well,” Mabel said brightly, “That’s nice! Are you gonna pass all your online classes?”
“I already have,” he said. “Since I finished all the units, the dean gave me permission to take the finals. I did them yesterday.”
“Nerd sighting!" Mabel rolled her eyes, but she was grinning. "And you got all A’s.”
He smiled. “I’m fairly sure I got all A’s. How are your classes?”
Mabel gave a mild shrug. “Just two left. The Art History’s a breeze. I’m getting an A-plus in it without even trying, hardly. I can take the final in that in about two weeks. Math is more frustrating. But I’ve got a middle B, and I’ve got until May 15 to catch up on everything and take the final. If you’ll help me with my homework, I can make an A minus in that, I think.”
“I’ll help.’
Mabel set her phone down on Dipper’s bedside table. “Good thing Mom didn’t want to make it a face-time call, with me naked and my boobies different sizes. What did we do wrong?”
Sitting on the edge of the bed, she did look funny. Her left breast was still plain-vanilla Mabel size, a 34 B-cup. The right one was the size of a watermelon and she had to either cradle it in both arms or lean forward to let it rest on her thighs.
“It’s like I said.” Dipper picked up the shrink/grow ray. “A flashlight doesn’t have precision controls. I can narrow the beam to do things like making your nipples longer, but for the whole boob job, it has to be wide. Getting it perfect is all in the timing. You've just forgotten how to judge the time. Let me work it.”
“Okay, but how does Righty look? I mean, is it tempting?”
“Intimidating,” Dipper said.
“Pull on the nipple. I wanna feel.”
Dipper closed his fingers around the pink nipple, now the size of a healthy cow’s teat, and squeezed and pulled.
“Interesting,” Mabel said, shivering. “Little bit too sensational for me. All right, Master of the Shrinker, get it back so it’s a size or a size and a half bigger than Lefty. And don’t you dare make me flat!”
“Lie back. No, don’t hold your boob. I don’t want to make your arms weird. That’s good right there. Hold very still,” Dipper said, clicking the crystal in its makeshift holder. “Real still. Don’t get your hands in the way or anything. I’m going to do this in short flashes.”
He flicked the shrink light on and off several times, and Mabel’s giganto tit deflated until it no longer looked like a boob-shaped beachball. Finally she stood up and turned in profile. “Too big?” she asked.
“Yeah, still looks heavy and a little floppy. Turn around so I can see the other one. Hmm. Yeah, I think we need to make the big one a third smaller and then enlarge the left one about the same amount. No, don’t lie down again. Just sit on the edge of the bed, shoulders back. Keep still, now.”
Twenty minutes later, Mabel was caressing her new, larger tits. Dipper had given her nipples special close-focus attention, and now they stuck out like the last joints of thumbs even when not erect, and her areolas were bigger and puffier. The color had become a richer pink, too. “Mabel likes!” she announced. “Let’s take ‘em for a test suck!”
By that time Mabel and Dipper had been naked together for three hours and it no longer seemed quite so creepy for her to lie back in bed with him on top, supporting his weight with knees and elbows, and his lips on her teats. “Feels real good to me, Dipper,” she purred. “You like that?”
“It’s good,” he said. He didn’t add that having the springy erectile nipples pressing against his tongue was unexpectedly erotic. He had angled in so his penis would not poke against Mabel’s stomach or thighs or, God forbid, her pussy, and he kept it squashed into the mattress, but it was beginning to want to run free again.
Mabel put a hand on the back of Dipper’s hair and caressed him, running her fingers through. “Try teasing my pussy while you do this,” she whispered. “I think that would be real special!”
“If I do, you have to spend two hours every day on your college work.”
“Highway robbery! But, yeah, I promise. Get those fingers bizzay!”
Dipper had been suckling her left breast while fondling her right. He shifted his position a little and glided his left hand down the increased slope of her boob, across her lower chest and onto her abdomen. He teased her bellybutton, putting his forefinger into the little fleshy well and making circles.
“Oooh, makes me shiver, but that’s not the hole I want you to explore,” she complained mildly, but her voice had a breathy, husky tone. So he moved his fingers slowly down, to the bulge of her mons veneris. He toyed with her pubic hair.
“Is my muff too thick?” she asked, a little anxiously. “I’ve been thinking it might get in the way of mouth stuff. Do you think I should trim it more? Wax it?”
He stopped sucking her nipple long enough to say, “It looks like you already shaped it."
"Yeah, just made a design. So shave or wax or what?"
"I don’t know about waxing. Sounds painful.”
“The girls tell me it’s not so bad after the first time. I could try it myself at home.”
“You’d need wax.”
“I got hundreds of half-used-up crayons!”
“I wouldn’t try it, Mabel.”
“Hey, Nippy’s getting cold. Warm her up. Yeah, that’s nice. Ooh, there your fingers are! Try to make me cum again while you suck on my nipples. I want to know what to expect when a real boy does this.”
“Excuse me?”
“I mean a non-brother type real boy, dum-dum. Yeah, just rub the slit until the doors open and invite you inside. There, feel how wet I am? Now use that. Up and down, up and down.” She squirmed. “This time put two fingers inside, deep as you can. Go slow! I want to see if we can find my G-spot. The girls say that cumming with your clitty is fun, but cumming deep in your pussy is mind-blowing.”
Mabel’s hips began to move in a slow, lewd rhythm. Dipper could smell her secretions, the musky, feminine aroma that said, “I want you!” It seemed to him that even her nipples were secreting something tart and practically intoxicating, but he couldn’t see anything. His dick didn’t care that the feelings and the aromas were coming from his sister. His dick loved them and started to rage.
Dipper had to shift position to finger-fuck his twin sister. Mabel caught her bottom lip in her teeth and now was thrusting her hips as if really having full-tilt heavy-duty sex. Dipper could hear the slurping sounds his fingers made. His first and middle fingers curled beneath her pubic ledge in the hot depths of her. Experimentally he started to wiggle his fingers independent of each other, and she sped up her humping movements.
“Don’t stop what that is you’re doing now whatever it is it’s fucking great!” Mabel gasped all in one breath. “Faster! Harder!”
Then Dipper must have hit her trigger, because her voice went way up in the soprano range, as she shrieked, “OHHH EMMM GEEE, I’M THERE!”
He felt her whole pussy clench and convulse, and again she squirted. This time he had wit enough to try to catch some in his cupped palm. As Mabel went slack, gasping, panting, and cooing, he said, “Huh. Well, it’s not pee!”
“Unnhh,” Mabel moaned. “You got a sample? I want to see.”
She reversed until she more or less lay on her hip and reached to cup her hand beneath Dipper’s. He held about a teaspoonful of a thin, milky liquid that had squirted from Mabel when she orgasmed.
“Felt like there was a lot more of it,” she said. She sniffed it. “Not much smell.” She dipped a finger in. “Slickery. I bet this is more lube! What does it taste like?”
“I didn’t try it!”
“Let me!” She steadied his hand, bent her head, and licked his palm. Then, her cheek bulging a little, she sat upright and turned her eyes upward like a wine connoisseur at a tasting. “Hmmm.”
“What is it—mupphh!”
She had grabbed him and given him an unexpected kiss, open-mouthed, tongue to tongue. When they broke apart, clingy clear liquid strings linked their lips. With her forehead pressing against his, she whispered, “What do you think brobro?”
“Umm . . . kinda faintly sweet,” he said, surprised. “Not like sugar or anything, but a little acidy taste, I guess, but sweetish, too, like, um, some kind of diluted fruit juice.”
“Aw, Dip!” Mabel said. “Look at your dick, all stiff and hard. Hey, long as we’ve got the no pussy-poking rule, how about a boob job? With this new rack, I bet I could give you a good one!”
“Um. . . . “
“Don’t tell me you don’t know what they are!” she scolded. “I know you watched ‘The Boobs and the Tube’ on the sly, and you saw this woman with humongous knockers take on three guys, one at a time, and she wound up with her face drenched in cum!”
“How did you even—”
“I heard you through the door and caught the moans and the yelling the soundtrack was making. Later I checked your phone history! It’s a good video. Titty-fucking looks like so much fun!”
“Hey, I don’t pry into your private emails and things,” he complained.
“Yeah, but I’m the snoopy-snoop! Here, let’s fix this. Gimme the pillows. There we go. Sit. Spread your knees! Now here I am, kneeling on the floor before you naked with my big hot tits on your thighs. You scoot your butt closer, sit on the edge of the bed and let me put that big steamy wiener into my soft titty-buns.” She looked up, face tilted, grinning. “You like it?”
“Feels different,” Dipper said, imagining Wendy doing this. “But really good.”
She cupped her tits with her hands, pressing them soft against his shaft. Then she began to move them, stroking him with the soft, warm globes. “Wanna continue until we hit a gusher?”
Dipper put his hands on her shoulders. “I don’t think so. I mean, it does feel good, but a guy can’t just cum and cum indefinitely. Right now I think it might hurt if we forced it. Give me about a while to rest and then . . . we can try.”
“Okay!” She jumped up, breasts bobbling. “Whoa! Look at these puppies! Hang on a minute!”
Dipper sat on the edge of the bed, wondering what fresh hell he had walked into. Maybe Mabel was right—maybe things like masturbation and even oral gratification weren’t real sex, not unless you got right down to it, penis into pussy, pumping and cumming. “Technically not sex,” he reassured himself.
Mabel was pinching and stretching her nipples, grinning. “Better than Smiley Dip.”
“Uh, Sis, why don’t you go to your room for a couple of hours? Maybe finish up your art class assignment, the one that's so easy? I’d like to call Wendy and tell her we’ll be coming up tomorrow.”
“Good idea! If I can turn in the last assignments in the class, then I might see how my nips like Mr. Buzzy. If talking to Wen-Wen gets you all hot and bothered, these boobs are made for titty-fucking!” She bounced out, jiggling.
After a moment’s hesitation, Dipper pulled on just his shirt and then moved the pillows to their proper location and sat on the bed, leaning against the wall. He used the face-time app to call Wendy’s number.
She answered right away, her freckled face smiling at him from the phone screen. “Dipper! I saw I missed a call from you, and I did mean to return it, but I’ve been crazy busy, man!”
“Yeah, well,” he said, grinning foolishly.
Wendy looked a little concerned. He didn’t recognize the background, but she wasn’t in her family home. She said, “Dip, are you sick, dude? Your face is like real red.”
“Just excited. Mabel and I got some good news. We’re coming back to Gravity Falls tomorrow, and we get to stay the whole summer!”
“Fantastic!” Wendy said. “You can bring my birthday present, ‘cause you’ll be here for that! I know what I want, and you don’t even have to tie a bow around it!”
“Yeah, I can’t wait. The down side is, Dad’s just getting over the virus—”
“I should’ve asked already, is he okay?”
“He’s getting better, but he needs like two weeks of quiet rest, and Mom’s sending us up to the Falls with Gruncle Stan because he says the pandemic isn’t in the valley at all.”
“Yeah, he’s right. Too bad Old Man McGucket didn’t plague-proof everywhere else!” Wendy looked around and then lowered her voice: “I’d flash my boobs for you, but I can’t. See, my brother Marcus just had the same crud. Fact is, I’m up close to the Washington State border, taking care of him. My Dad’s with us, but he’s helping with a timber job until next Thursday, and then he’s gonna stay here for another month, 'cause he bid on a big clean-up job and it looks like he'll win the bid. The virus 'round here is still going strong, but he's making his crew be real careful. I’m vaccinated and boosted and so far I didn’t get it, but after today, I gotta wait another five days and trest negative again before I can come back to the Falls. Bummer.”
Dipper’s heart sank. “Aw. I wanted to see you the minute we get there.”
“Sorry, man. Bright side, my vaccinations are holding, and Marcus had what was more like a nasty flu, little fever, aches—I hear you, Marcus! Give me a damn minute!” She exhaled. “He’s a rotten patient. I have to go fix him some food now. After you get in, I’ll call you tomorrow night with updates and maybe some hot pics. Oh, don’t be surprised when you get to the Falls. McGucket’s crew will have to decontaminate you and all your belongings.” She lowered her voice. “Word of advice, man. Don’t pack condoms unless you don’t mind them embarrassing you. I can stock up on ‘em when I’m driving home. So I’ll see you in six days, tops, man. Love you!”
“Love you, too.”
Maybe it was all the ejaculating that wore him out, or maybe it was his disappointment on not being able to see Wendy tomorrow, but Dipper lay back and dozed. Until late afternoon, in fact.
Mabel woke him up as she came in without knocking. “Finished another Art Unit! Geeze, Dipper, put some pants on. Hey, I’m packing for the trip. What do you think about this for a flirty outfit?” she asked, putting a hand on her hip and sticking out her leg in a bimbo pose.
She was wearing a sheer, tight, white crop-top, so thin that her pointed pink nipples showed through, every dimple and bump on display, and the fabric clung to her like a second skin. Her midriff was bare, and she wore tight blue stirrup leggings, also sheer, with a three-inch-wide lace strip up the side of each leg, proving that she wore nothing underneath. She turned deliberately and bent over to grasp her ankles, her butt toward him. “How’s the view?”
“Really explicit,” Dipper said. “You’d need some shorts, though. When did you even get—”
She turned around and stood up again, shoulders back, putting her tits on display. “I bought these garments on the sly, same time I bought Mr. Buzzy. I thought I would wear a sports bra under the top but look at ‘em!” She waggled her shoulders. “Now that I’m bigger, the fabric rubs my nips and makes ‘em stick way out! And check this out.” She turned to face him head-on, arched her back, and spread her thighs. “Behold the classic camel toe! Will this intrigue a boy?”
“I don’t know about intrigue,” he said. “It won’t leave him very much to imagine.”
She came over and hopped onto the bed. “I noticed it didn’t make your penis—can I just say dick? Penis seems like medical. Anyway, the outfit doesn’t make your dick hard. It’s floppy again. What happened? You didn’t jack off while I was on the computer, did you?”
“No, I just got disappointed. Wendy’s away from the Falls for the next week,” Dipper said.
“Aw, shit.”
Dipper had to laugh. “Since when do you say shit?”
“Since I outgrew poop. I can say ‘em all now, borobro. Shit, piss, damn, tits, pussy, clitty, even cunt and asshole. Or dick, balls, and thick, juicy cum. Cock. Prick. Fuck. Screw. Sixty-nine.”
“If you paid as much attention to your college courses as those videos—”
“Yeah, yeah. Let’s look on the bright side. With Wendy away for a while, we don’t have to rush our training! Plus we’re gonna be alone together in the Mystery Shack for nearly a week. You and me can hone—is that a word?” Hone?”
“Yeah, means sharpen.”
“Does it? Well, we can perfect our sexy techniques by practicing with each other. By the time you get together with Wendy, you’ll kiss her and lightly touch her, and she’ll be all like—” Mabel put the back of her hand against her forehead and pretended to swoon—“Oh, Dipper, your kiss and touch are like magic, igniting the flame in my heart. My body and soul are yours! Wanna like fuck, man?”
“That’s not like her at all.”
Mabel peeled off her transparent top and her tight leggings. “It will be, Brobro. I promise, it will be. Now . . . where were we? Oh, yeah, boob job! Hand me those pillows and take off that fucking shirt.”
“Fuck, yeah,” Dipper said.
***
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