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Depravity Falls	By : GeorgeGlass Category: +G through L > Gravity Falls Views: 15965 -:- Recommendations : 4 -:- Currently Reading : 5
Disclaimer: I do not own Gravity Falls or its characters. I made no money from writing this story.

Chapter List
- 3
- 4
- 5
Chapter 4: Hidden Vagenda
During the next few days, Mabel got busy—in various senses. It was Fourth of July week, the start of the high season for tourism, so there was plenty to do at the Shack. It was also a week for parades and other festivities, which Mabel attended with Grenda and Candy. On top of that, Dipper had made a few visits to crash site Omega by this point, and he had found a new mystery to latch onto.
“Mabel, look at this,” he said one evening.
He placed a photograph with yellowed edges on the bed. It showed a flat metal counter to which five objects—devices of some kind—were attached with clips. There was a mirror-like surface in front of the counter.
“When Great Uncle Ford first found Crash Site Omega,” Dipper went on, “he took pictures of everything, including this table with these five artifacts. But look at this picture I took yesterday.”
He showed Mabel a picture on his phone. It showed the same metal counter, but there were only empty clips where the five gadgets had been.
“Great Uncle Ford told me nobody else knew where the crash site was. So who could have taken the artifacts? They aren’t in Ford’s lab—I’ve searched it from top to bottom.”
“Well,” Mabel mused, “wasn’t Old Man McGucket his assistant? You know, back when he was Middle-aged Man McGucket? Maybe he took those gizmos.”
“I guess that’s possible. But even if McGucket has them, he probably doesn’t even know it, after everything that memory-wiping device did to his mind.”
Dipper put a hand to his chin and added, “But Great Uncle Ford left us something that might help. I’ll look for it in his lab.” Then he smiled at Mabel and said, “But right now, you wanna…”
Mabel grinned and replied, “Oh, I definitely wanna.”
Mabel’s new sex life with Dipper presented another major demand on Mabel’s time, although she didn’t mind that at all. After that first night, they’d done it at least three times a day—mostly in their bedroom, but also once in the storeroom when they were feeling particularly brave.
On the Fourth itself, after an extra-busy and thus extra-profitable day at the Shack, Soos again treated everyone to dinner at Greasy’s. The diner had only so many tables for six, so Mabel, Dipper, Soos, Melody, Grandma Soos, and Wendy ended up at the same table as last time.
“How come you’re with us tonight, Wendy?” Mabel asked. “Isn’t your family having a barbecue or something?”
“That’s why I’m here,” Wendy replied. “Every year, my dad tries to grill, and every year, the fire department has to get involved. The man does not know when to stop with the wood and lighter fluid. I decided I’d rather not get my flannel singed this year.”
Just then, Pacifica appeared at their table. Mabel felt a stab of guilt; she’d been meaning to get in touch with the girl to hang out, but having been so busy lately, Mabel always had an excuse for not doing it.
“Hey, guys,” Pacifica said. “Are you going to go watch the fireworks later?”
“Yeah,” Mabel replied. “Dipper and I are gonna meet up with Candy and Grenda and watch from Elevation Hill.”
“Oh,” Pacifica replied. “That…sounds nice. I, um, I don’t have any plans, myself.”
Mabel’s guilt intensified from an ache to a pang. So she steeled herself and asked, “Do you want to come with us? We’re planning to meet up at eight-thirty.”
“That’s perfect!” Pacifica replied. Then, seemingly trying to tamp down her enthusiasm, she went on. “I get off at eight tonight, so I’ll just go home and change and then meet you guys on the hill.”
Then she pulled out her order pad. “Now, what can I get you all?”
Everyone placed their orders, and soon, Mabel was digging into that night’s special: the Ameriburger with a side of Liberty Slaw. Dipper grimaced at the red-white-and-blue coleslaw, but Mabel ate it with gusto.
At one point during the meal, after Pacifica refilled everyone’s water glasses, she said, “I’m about to go on my fifteen-minute break. Lazy Susan will take care of you until I come back.”
“Enjoy!” Soos replied, and Melody gave the girl a friendly wave.
Mabel watched Pacifica walk away, idly curious about how the blonde girl would spend her break. But instead of going somewhere in the back of the diner, as Mabel expected, Pacifica walked past the counter and gave one of the men sitting there—a trucker, judging from his mesh-backed baseball cap that read ROAD DAWG—a single tap on the shoulder. Pacifica then went through the door into the kitchen, and the trucker got up and went out the front door.
Maybe they’re friends or something, Mabel thought. If Pacifica has been working here since last summer, she’s probably gotten to know a lot of people.
***
The next day, the Shack wasn’t set to open until noon, so Mabel finally got a chance to go into the woods to see Dee. Mabel was glad for her shoe-lights, because as she approached the rear of the cave, she very nearly stumbled over something lying on the cave floor. She didn’t remember such a large rock being there before. Had she just failed to notice it during her two previous visits?
“Hello, Mabel,” Dee’s disembodied voice said. “Would you be so kind as to straighten me up?”
“Huh?” Mabel replied.
She looked up at the cave wall where Dee’s statue should have been and saw nothing but a big cavity in the rock. Then Mabel looked back down and realized that the rock at her feet looked like the back of a broad-hipped woman.
“Dee!” Mabel shouted, grabbing the statue’s head and using her arms, back, and legs to pull the sculpture upright. “What happened?”
“Oh, nothing bad,” Dee replied. “This is actually a rather good thing. Your activities with your brother have enabled me to free myself from the cave wall.”
“Really? How?”
“As I told you in our last chat, every new sexual act you perform makes us both a bit more powerful. In this case, it made me strong enough to detach myself from the rock.”
Mabel put a finger to her chin as she said, “That’s cool and everything, but I don’t see how lying on your face is better than being on the wall.”
“Well, if nothing else, it makes me a bit more portable. In fact, if you would care to drag me outside, we could continue our conversation in the sunshine instead of in this musty cave.”
It took all of Mabel’s strength to haul the stone statue across the cave floor and outside. By the time she reached a spot just to the side of the cave entrance, Mabel was exhausted and sweaty. Yet she was pleased to have managed the task. But before she could congratulate herself on a job well done, a pang of guilt shot through her.
“I’m sorry, Dee,” Mabel said, still panting from the effort. “I’ve been so busy doing the horizontal mambo with Dipper that I haven’t had a chance to come see you. How long were you lying on your face like that?” Then her eyebrows rose as her guilt suddenly ratcheted upward. “Oh no, you’ve been all by yourself in that cave this whole time! Do you get lonely? Oh, I’m such a jerk!”
“No, no, Mabel, don’t worry about me. I can see many things, so I never feel alone. And your sexual adventures are time well spent.”
Mabel’s distress gave way to relief and then joy as she replied, “Yeah, sex has been totally amazing. And we don’t even need the chocolate anymore!”
“The chocolate,” Dee said, “was just to get you and your brother over the hump…as it were. Now, your own sexiness and Dipper’s teenage horniness should be all you need to keep up the naughty fun. In any case, it sounds like things are going swimmingly.”
“Nah, we haven’t done it at the pool yet. I think Dipper’s scared of that Mr. Poolchek guy. Plus, I don’t really want to be thinking about Mermando when I’m boinking Dipper, you know?” Her brow furrowed as she added, “Especially ‘cause now that I think about it, I’m not even sure if Mermando had a wiener. I mean, he was a fish from the waist down, so where would-”
“Let’s not get off track, my dear,” Dee interrupted. “I simply meant that things are going well with you and your brother.”
“Oh, yeah, definitely! We’re doing it, like, all the time. We even sneaked off during work today and did it on the roof.” She sniggered. “I think I still have shingle-prints on my butt. And man, after the fireworks last night, we came home and made some serious fireworks of our own,” she finished with a giggle.
“Excellent!” Dee replied. “In that case, I think you’re more than ready to get started on your vagenda.”
Mabel looked at Dee quizzically. “Um, my what now?”
“Your vagenda. It’s a list of all the sexual things you might want to try. You can add new items to the list whenever you want, and when you do one of them, you check it off. It’s like birdwatching, but with orgasms.”
“That sounds fun!”
“I knew you’d think so. So, what do you want to put on the list?”
“Um, I want to, uh, do it in every room of the Shack!”
“Really? Even in Grandma Ramirez’s room?”
Mabel grinned creepily. “Especially in Grandma Ramirez’s room.”
“That’s my girl! What else?”
“Um, do it in the woods!”
“That’s good, too, but there’s more variety to sex than just having it in different places. Let’s talk about different ways of doing it.”
“Like what?”
“Well, oral sex, for starters.”
“You mean, his thing in my mouth? Or his mouth on my thing?”
“Yes and yes, but you’re really going to have to start using words other than ‘thing.’ In fact, I’m giving you that as a homework assignment: The next time we meet, I want you to have learned five new words for ‘penis.’”
Ideas flooded into Mabel’s head. Maypole! Love-Plunger! Shprongulator!
“And I do mean ‘learned,’ not ‘made up,’” Dee clarified. Mabel tried not to show her disappointment.
“In any case, yes,” Dee went on, “I mean the coming together of mouths and genitals. Also, have you ever thought about having sex when one of you is tied up?”
“You mean, like, with ropes and stuff?”
“Ropes, chains, extension cords, hair ribbons, pink drapery cord, thong panties, whatever you’ve got lying around.”
Mabel chuckled at the mental image of many pairs of colorful thong panties—something she’d learned about from music videos—lying around her and Dipper’s bedroom. Then her mind moved on to the implications of what Dee had just said, and she frowned a bit
“Yeahhhh,” Mabel replied skeptically, “I don’t think Dipper would ever let me tie him up again.”
“‘Again?’” Dee asked.
“There was an incident when we were six.”
“Ooooh, children being naughty. Tell me more.”
“I might have tied Dipper to the leg of the piano with dental floss and then put some of our mom’s makeup on him. Mom was really mad at me, and it probably put Dipper off being tied up for, like, life.”
“I see,” Dee replied. “Well, how about letting him tie you up?”
“That would be an easier sell, I guess. But what’s fun about being tied up?”
“Mostly the role playing,” Dee replied.
“Oh, no no no no!” Mabel objected. “That role-playing stuff is so boring! Dipper made me do it once, and there was all this math, and character classes, and what’s the difference between splint mail and banded mail, and then we got attacked by an evil math wizard! I mean, not that there would be any other kind of math wizard.”
“My dear, that’s not the sort of role-playing I mean,” Dee replied. Then, in a high-pitched voice, she said, “‘Oh, Dipper, please don’t rape me! I’m ever so helpless, and I couldn’t stop you from shoving your big, hard cock deep inside me and fucking me until I scream.’”
“Okay, yeah,” Mabel said, giggling. “That does sound kinda fun.”
“Another fun thing,” Dee suggested, “would be to let Dipper put his cock up your ass.”
Mabel’s eyes widened. “Like…in my butthole?”
Dee sighed. “Yes, in your ‘butthole.’”
“Does that feel good?”
“Lots of girls think so. Haven’t you ever tried pushing anything into your ass?”
“Welllll, there was this time in the bathtub when I was five and I put one of Dipper’s army men up there, but that didn’t feel so great.” She sniggered. “But it was pretty funny watching Dipper play with it the next day.”
“An army man?” Dee replied. “Goodness, why not just go all in and use a live porcupine? Believe me, it feels a great deal nicer when you use something of the right shape—most especially a boy’s cock. Try it, and you’ll see.”
“You really think I’ll like it?”
“You might even love it. But don’t forget to use some lubricant.”
“You mean like-”
“I mean,” Dee interrupted, “J-X Jelly, or vegetable oil, or something like that. Not anything you squeeze from a rectangular metal can you found in the garage.”
Mabel nodded slowly, disappointed that her guess about what kind of lubricant to use had been exactly wrong, but also glad that Dee seemed to know her well enough to help her avoid making such mistakes.
“Well,” Mabel replied, “you haven’t steered me wrong so far, so…I guess I’ll see if Dipper wants to try it.”
“Oh, he’ll most certainly want to try it. Especially if you make him the offer in the sexiest way you can.”
“No problem! I’m starting to get good at being sexy.”
“You know, I do believe that’s true,” Dee replied. “Which reminds me: Mabel, as a budding sexual adventuress, you need to start upping your underclothing game.”
“Ooooh, right, I definitely need fancier undies,” Mabel said. She tapped her finger against her chin pensively, then cried, “I know! I’ll take my nicest pair of blue panties and write my name across the butt in rainbow sparklies!” Looking upward, she mused, “Now, I know I packed my glue gun, but did I remember to bring-”
“Mabel,” Dee interrupted, “that’s not what I’m talking about. I mean that you need some lingerie. Something sexy and enticing that, when you wear it, will make your brother even more enthusiastic about shagging you ragged every night.”
“Hmm,” Mabel replied, unsure. “I, uh, I guess I’ll see what I can come up with. Even though Soos pays us better than Grunkle Stan, I don’t think I can afford anything from the Underglory catalog.”
Thinking of money made Mabel glance at her watch. “Welp, I’ve gotta get going. Wendy’s out sick, so I’m subbing in for her at the gift shop. And like Grunkle Stan used to say, those customers aren’t gonna fleece themselves!”
“Then I’ll see you later, Mabel. And don’t forget what I said about lingerie.”
As Mabel walked toward the edge of the clearing, she muttered, “Still gonna use my glue gun.”
“What was that?”
“Nothing! See ya!”
***
That afternoon, as they were getting ready to close up the Shack for the day, Mabel approached her brother and said, “Hey Dipper, you want to go to the hobby shop?”
Dipper gave her a little leer as he replied, “Are you sure you wouldn’t rather…?”
Mabel chuckled naughtily and said in a low voice, “Let’s just say the purpose of this trip is to spice things up a little.” Then, at a normal conversational volume, she added, “Besides, they’ve got all kinds of spaceship models there.”
“All right,” Dipper replied. “Let’s go check it out.”
***
The hobby shop was downtown. Mabel had visited it several times the previous year to purchase arts and crafts supplies, and she was looking forward to chatting with the nice, mom-aged lady who owned the place.
But when Mabel and Dipper stepped through the glass door of Hobby Horse and walked toward the counter, Mabel was surprised to see, not a middle-aged woman, but a boy close to Mabel’s own age.
It occurred to Mabel that this could be a chance for Dipper to make a friend of his own here in Gravity Falls. A friend who’s shiny black hair and flawless olive skin. Mabel wouldn’t mind seeing on a regular basis. So even though she knew exactly where to find the supplies she wanted, she walked up to the counter, Dipper at her side.
“Hi,” she said to the boy. “Where can I find the glitter?”
The young man smiled at her. “Aisle four.”
“Thanks! I’m Mabel, and this is my brother Dipper.”
“Hi, I’m Darren. Are you guys new in town?”
Dipper spoke up. “We’re here for the summer.” Then he pointed at some shelves a few aisles away from the register. “Hey, are those models from Space Troopers?”
“Yep. We’ve got models of every ship from the Galacticorps and the Slagon Empire. Even that one-off dropship from episode twenty-seven.”
“‘Raid on Volturno’?” Dipper replied. “That’s my favorite episode!”
“Oh man,” Darren said, “when they go into that cave-”
“-and realize that they’ve accidentally found a Slagon Level Two command center?” Dipper finished. “That was the best!”
Happy to leave the boys to their nerdy banter, Mabel was starting to head to aisle four when Darren came out from behind the counter and escorted her there.
“What kind of glitter do you need?” he asked.
“Rainbow!” Mabel replied brightly.
“Do you know how much?”
Mabel stopped short of putting her hands on her butt and just tried to guesstimate the surface area she’d need to cover. “Um, I think one tube should do it. On second thought, better make it two. I’ve got a little more width back there now.”
“Um, back where?”
“Oh, uh,” Mabel stammered. “On my back! I’m making a T-shirt.”
“And your back is wider now?”
“Yeah, well, you know, I had a growth spurt. Plus we did a lot of pushups in gym class this year, so I’ve got more lats and delts and traps and stuff.”
“Ah.”
Mabel was doing the exact thing she had hoped never to do again: making a fool of herself in front of a cute boy. She stopped talking and took a deep, cleansing breath.
Remember, she said to herself, you’ve got Dipper now. You don’t need other boys to like you. Not like-you like-you, anyway.
Feeling rather more relaxed, Mabel continued, “Anyway, looks like you’ve got two different brands of rainbow glitter. Which one do you recommend?”
“Well,” Darren replied, “if you’re a rainbow purist, then you want the Craft Celebration glitter; the colors are strictly Roy G. Biv. But, if you want something a little offbeat, then try the Chromagic.” He gave her a conspiratorial smile as he added, “It has some colors that I’m not sure can be found in nature.”
Wait, is he flirting with me? Mabel thought. It had been a while since she had been the flirt-ee and not the flirt-er.
So she couldn’t resist the urge to make her tone just a little bit suggestive as she said, “Then I’ll take two tubes of the Chromagic. Oh, and I need some more ammo for my glue gun.”
“Actually, if you’re making a T-shirt, you might want to use fabric glue instead. It’ll make the glitter stick better—you know, so you don’t leave a rainbow trail on the ground wherever you go.”
Mabel tried not to chuckle at the mental image of rainbow sparkles falling from her butt like shiny, multicolored snow. And thinking about panties gave her another idea.
“Now that I think about it,” she said, “I could use some yarn, too.”
“Aisle six,” Darren replied with a decidedly non-salesmanly smile.
Dipper waved to Darren from the model section, and Darren went over to help him. So Mabel proceeded on her own to aisle six—where she found a familiar blonde girl.
“Pacifica?” she said, surprised. “I didn’t expect to see you…here.”
“You mean, at a place for people who can actually do things for themselves?” Pacifica replied. Then, before Mabel could deny that she had meant any such thing—even though she had—Pacifica went on, “Don’t worry, I get it. But these days, if I want something nice, I have to make it myself, so here I am.”
“So…” Mabel said, “wanna help me pick some yarn?”
“Sure.”
***
As soon as Mabel and Dipper got back to the Shack, Mabel grabbed a pair of panties and stuffed them into the bag with her newly purchased supplies. Then she told Dipper that she was going out to the shed to work on a secret project.
***
That night, Dipper didn’t even get the chance to turn out the light before Mabel approached him, giving him a long, smoky kiss.
“Hey Dipper,” she said as enticingly as she knew how—which was very enticingly, in her opinion—“wanna play our new favorite game?”
Dipper smiled. “Oh, heck yeah.”
Mabel pulled off her nightgown, showing Dipper her perky little breasts and her blue panties.
“Good,” she replied, “‘cause I’ve got a new way to play it.”
Dipper looked intrigued, which was exactly what Mabel had hoped for. “Oh yeah?”
Mabel turned around and pushed her petite bottom out a little to show Dipper the back of her panties. Using rainbow sparkles, she had written “Property of Dipper” across her ass. Dipper’s face lit up with a huge grin.
“This fine booty is all yours, Bro-Bro.” Then, cocking her hip to one side, she asked, “What’cha gonna do with it? I hear butt stuff is pretty fun. Wanna shove it where the sun don’t shine?”
Dipper’s eyes widened with both surprise and lust. “Yeah? You wanna try that? I mean, I’ve heard guys at school talk about it, but I didn’t think there were girls who actually wanted to do it.”
Mabel smiled, because Dipper had just given her the perfect lead-in for what she had planned to do next: bend over and grab the footboard of her bed, thus presenting her sparkly ass to him as she replied, “Does this change your mind?”
Dipper didn’t hesitate; he came right up behind Mabel and slowly pulled her spangly panties down, as though he were unveiling her ass. Then he let the panties fall down to her ankles, took hold of Mabel’s pale, firm asscheeks, and pulled them apart.
Mabel felt a surge of pride. She was getting really good at seducing Dipper. And she’d remembered to put something slippery on her little pink hole; luckily, Soos’ grandma kept a lot of manteca de cerdo in the fridge. Mabel didn’t know exactly what the white, greasy stuff was, but the package had a picture of a pig on it, so it was probably something fun.
“I can’t believe we’re gonna do this,” Dipper said eagerly. He’d let go of one Mabel-cheek so he could position his cockhead against her tight hole.
“Me neither,” Mabel said. The mere anticipation was making her so horny that she was starting to pant for breath. “Please, push it in. Just do it slow, okay?”
“Okay.”
He started to push, and Mabel felt her anal ring start to stretch open. Despite all of Dee’s encouragement, she’d been a little uncertain about whether she would actually like this. But now, all she wanted was for Dipper to open her up wider, because that stretching feeling was amazing.
“Oh yeah,” she moaned. “That feels good…Put it in more…”
The sensation changed as her hole widened to the diameter of the base of Dipper’s cockhead and his shaft began to sink in. There was no question that her brother’s dick felt way better in there than his army man. And as Dipper eased a couple inches farther into her ass, it felt better still, to the point where Mabel found herself babbling loudly.
“Oh God, it’s in my butt!” Mabel cried. “It’s in my butt and I love it in my butt and I want it deeper in my butt!”
“Oh hell yeah,” Dipper rasped, then pushed two more inches of his length into Mabel’s pink asshole.
“Aaah! Ah yes!” Mabel shouted. “Put it all in!”
Dipper sank into her until his pubic bone was pressed against the top of her ass-crack, making Mabel sigh with pleasure. Then she reached back, grabbed his hips, and pulled, keeping them pressed snugly against her ass and his cock buried as deep inside her as it could go. She could feel her brother’s balls against her pussy, but the main sensation she was savoring was that of her ass being fully penetrated by Dipper’s sweet cock.
“Ooooh, Dipper,” she moaned. “I feel so nice and full…”
“Oh, Mabel,” Dipper breathed, “you’re so hot inside…It feels so good around me…”
She moved her hands on top of his where they held her hips.
“Fuck me, Dipper. I wanna feel it move inside me.”
He eased most of the way out, then pushed back in, Mabel pulling with her hands to assist his pushing. In unison, they sighed with pleasure.
“Ohhhh,” Dipper exhaled. “Your little hole is soooo tight…”
“Oh, gosh, and your cock feels huge in there…” Mabel moaned. “Mmmm, keep fucking me…”
Dipper kept pumping her slowly. He was pulling most of the way out on every stroke; Mabel could actually feel her asshole grip the underside of his cockhead each time it slipped out and then back in.
“Mmm, Dipper,” she moaned, “you’re fucking me in the ass and I love it, I love it so much…”
“I love it too,” Dipper breathed, still pumping her slowly. “I could fuck you this way forever…”
In reality, though, it was only a few minutes before Dipper started fucking her faster. Not that Mabel minded.
“Ooooh, yes, Dipper,” she moaned. “Fuck my butt nice and hard…I wanna know…what it feels like…when you cum…in my ass…”
Perhaps in response to Mabel’s words, Dipper fucked her faster still. Mabel reached down and rubbed her love-button; she wanted to make sure she was ready to cum when Dipper was.
“Mabel,” Dipper panted, “I don’t think…I’m gonna last…much longer…”
“You don’t have to, Bro!” Mabel cried. “Just shoot it in me!”
That apparently was all Dipper needed to hear; he shouted “HUAAAAAH!” and shoved balls-deep into Mabel’s ass as he came. Mabel felt his hot seed shooting deep in her bowels, and then she was screaming “WEEEEAAAAAH!” as she came, too, her asshole squeezing her brother’s cock like crazy.
When it was over, Mabel straightened up and, feeling a bit delirious, almost fell forward against the headboard. Dipper caught her from behind and held her tight.
“You’re the best, Bro-Bro,” she said dreamily.
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Depravity Falls