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Spectrum	By : PineWreths Category: +G through L > Gravity Falls Views: 10257 -:- Recommendations : 0 -:- Currently Reading : 0
Disclaimer: I do not own Gravity Falls, nor the characters from it. I do not make any money from the writing of this story.

Chapter List
- 1-Spectrum
- 2-Part 2
- 3-Part 3
- 4-Part 4
- 3
- 4
Dipper was grinning ear to ear with the discovery that he now had sisters, plural. He gave them a knowing smile, saying “The copy machine is back up and working?”
One of the Mabels, the one dressed in the purple, nodded. She must have noticed him looking somewhat anxiously between his sisters, not sure of who to focus his attention on. The one in purple gave him a smile, one echoed by several other twins-Or are we now septuplets? he wondered idly-and raised her hand.
“Original Mabes over here, Dip Dot,” she said, giving him a slight bow, and continuing. “Yeah, I got Soos to give it a look; There’s a copy of his hand we had to set mousetraps out for, and I think his butt is still hiding somewhere inside the walls of the basement.”
Dipper looked cross-eyed for a second at the thought, shuddering with revulsion at the mental image, but his attention was drawn by his sister-the original, and otherwise indistinguishable from her new siblings apart from the color of her lingerie, lipstick, and hairbow.
She had taken a few long steps over, coming to sit on Dip’s leg, one of her legs looped over his other leg as he suddenly was aware of her bare and barely-covered flesh against his growing erection.
He coughed, part of him feeling like he was in public and wanting to cross his legs, but mostly his brain was overloaded with input; In every direction was his sister, dressed like something out of a dream.
Waitaminute, this basically is one of my dreams. It feels real, but with what we’ve encountered, anything goes.
He abruptly stood up, his sister in purple barely catching herself and avoiding a fall to the floor. Dipper backed up, putting the chair between him and his herd of sisters, suddenly feeling caged rather than excited.
“Ma-Mabes, this is-this is one of my dreams, like, exactly one of my dreams. It’s a good dream, don’t get me wrong, but I-this-this can’t be a coincidence.”
Purple-Mabel rolled her eyes, gesturing to one of her clones, and Orange-Mabel reached behind and into a bag in the closet, pulling out a manilla envelope. Stamped across the front in familiar handwriting was the title The Dipper File.
Dipper felt numerous parts of relief, and sudden brand-new and entirely-different panics set in. He had forgotten Grunkle Ford had printed out his thoughts from when he’d hooked him up to the repaired mind-reading terminal the year before he left the Shack; At the time, worries about Grunkle Ford reading it were quickly superseded by other imminent threats, and in the aftermath he had quite forgotten.
It was with a little whimpering noise that he realized that not only had Mabel gotten ahold of the file, she’d read it, at least in enough depth to stumble upon this.
A little part of the back of his mind tried in vain to fight the flood of anxious embarrassment he could feel washing over him. As Orange-Mabel handed the file off to Purple-Mabel, she kept eye contact with her brother, winking before mouthing words for him to lip-read: I read everything. The wink she gave him set parts of Dipper’s mind and imagination whirling, even as Purple-Mabel flipped open the file.
She thumbed to a post-it marked section, muttering to herself for a moment as she read. Behind her, the other six Mabels were occupying themselves as their brother was brought up to speed. Orange-Mabel was rubbing under the chin of a lark, Optimus, who had hopped down to perch on her finger as she giggled. Green-Mabel was braiding Blue-Mabel’s hair, and Indigo-Mabel…
Dipper swallowed. Indigo-Mabel had already discarded her teddy top, toying with a nipple as one hand idly rubbed her panties. She looked almost bored, but Dipper could see her breath rising and falling in short breaths. She looked up at Dipper, catching his eye as she opened hers, and with a grin, nodded back over towards Orange-Mabel.
Orange-Mabel had leaned to sit almost casually against the open closet door, her knees drawn up in front of her, and she was idly tapping a candy cane against the visible damp spot at the base of the fabric between her legs.
Dipper coughed, groaning quietly and mostly internally with frustration. He was quite certain no Christmas candy like that would have just been lying around, meaning she specifically bought that to fuck with him based on another scenario he’d fantasized about, this one with a distinctive holiday theme.
That particular thought wasn’t one Dipper remembered having while Grunkle Ford was checking him, but Dipper had idly wondered about that at times. He went a mottled scarlet and white of blushing and paling, as Orange-Mabel answered with a knowing grin his unvoiced question on his face about if she’d read that thought in particular.
Finally, Purple-Mabel found the entry she was looking for, and began reading aloud. “Lesee here, Oh man that dream with the rainbow party, each girl had Mabel’s face. Never wanted to wake up from that one, although, come to think of it, that sounds a bit morbid. Eh, whatever, it’s not like Grunkle Ford is-wait, why is paper coming out of the side of the OH FUCK NO FUCKFUCKFUCK UMMMM puppies and rainbows and kittens and mysteries and anything innocent, just don’t picture your sister, don’t imagine what Mabel was doing and the noises she was making as she sucked-Dammit. Puppies and rainbows and kittens and mysteries and-”
She snapped the file shut, giving him a wide, shit-eating grin. “I managed to find an article online about what a ‘rainbow party’ was, and that got me thinking, and I shanghaied Soos into helping me fix up the machine. A quick stop to get ink and paper, and then here we are!”
The other sisters let out various giggles, although one turned into a bit of a moan as Indigo-Mabel was preoccupied still on the bed. Purple-Mabel looked over at the sound, as did most of the other sisters, and various nervous giggles and blushes were seen and heard. Dipper couldn’t help but notice that for most of them, nipples had begun to perk against the lace fabric, and they crossed their legs or cleared their throats.
Dipper turned to the original Mabel, her purple lipstick framing a wide, toothy grin of excitement, and chuckled a bit wistfully. She cocked her head, saying “What?”
He smiled at her. “I read up more on rainbow parties a few months after that; Turns out it was made up, all bullshitted and people gobbled it up.” He coughed awkwardly as one of his sisters giggled at the accidental innuendo, and gave her an awkward shrug.
Purple-Mabel scowled at him, hands on her hips, before cracking a lascivious wink and grin at him. “Well, Dippingsauce, no time like the present to make it real.”
Dipper let out a little squeak of excitement, mirroring those his sister occasionally made, as the sheer realization hit like a ton of bricks and countless mastrubation fantasy sessions threatened to become an amazing reality.
An unexpected happy tear blurred the corner of his eyes, and he choked out a muted “Th-thanks for this, Mabes,” as he realized the effort his sister had gone to for this, just a throwaway sex fantasy.
There was a chorus of “Aww"s from around him, and in unison they replied "No problem, Dip,” before breaking into a rash of giggling fits.
Dipper leaned back in the chair he had returned to, rubbing his birthmark as he had another bout of sister overload. “So, um,” he said, looking around at his newfound sisters, “Did…did you all want to be called Mabel, then? Because that seems like it’s gonna get real confusing, real fast.”
Another bout of giggles ensued, and the purple-clad Mabel in front of him shook her head. “We tried that, and we also tried numbers. For a while we went by colors, but eventually we all got a nickname.”
She stood up, the spectrum coming back into place as Indigo-Mabel got into line and struggled to reclasp her teddy, her face slightly flush with both embarrassment and arousal. Purple-Mabel pointed to the sister clad in the red teddy, thong, hairbow, and lipstick, and in order of the rainbow re-introduced Dipper to his sisters.
“We figured we should each meet you one-on-one for the day, and so you’ve actually spent the last week with each of us.” Dipper nodded, having guessed that after seeing the matching yellow lingerie on the Mabel with Optimus the meadowlark, reminding him of her yellow sweater that day as well the day she had the bird.
“So first you’ve got Mare,” she said, as his red-clad sister gave him a little wave and a toothy smile.
“Next to her is Belle.“ His sister in the orange lingerie tapped the candy cane against her teeth with a mischievous grin, and Dipper swallowed and shifted to cross his legs. In a husky voice, she said "You can also call me ‘Juicy’ if you want, Dip.”
This was met with a several snickers and sets of rolled eyes, as Indigo-Mabel said in an annoyed voice “Belle, stop trying to make ‘Juicy’ happen.” Belle’s smile pouted for a second, but then she grinned and flicked her tongue across her lips before shooting back “I seem to recall a certain sister having no problem calling me that a few nights ago.”
This caused Indigo-Mabel to blush bright crimson and cough while looking at a blank patch of ceiling. The other Mabels laughed, Green-Mabel making a little “Ooh!” of aroused amusement, Dipper cocked his head a bit in confusion. He turned to Purple, original Mabel, before realizing himself and trying to address the group as best as he could. “Um, Mabes, you’re not normally that horny. Or sporty. Or-” and he looked at Yellow-Mabel, who was busy feeding Optimus a sunflower seed, “-princessy. What’s up with that?”
She smiled, and shrugged. “The printer had a ‘Spectrum’ setting, I guess to do color tests and stuff. There were two toggles for it, ‘P’ and ‘M,’ and I chose ‘M’ for Mabel!”
Her triumphant grin had him chuckling again, and she gave a rueful grin as she explained “We figured it probably stood for Physical and Mental, which is good; While I think I could rock green skin, that might have been a bit more noticeable by you and Grunkle Stan.”
He nodded, as she cleared her throat and continued the introductions. “Over there with Opti, that’s May, or if we’re using Dip’s nickname, Princess.” She said the name with a bit of a long-suffering tone, and Dipper noticed several of the other Mabels looked slightly disappointed at not getting that moniker. May evidently had no qualms about it, grinning at Dipper as she fed her lark another seed.
“Then there’s Meg-” she started to say, as Indigo-Mabel interrupted with “Gabby!” Meg-Mabel blushed with a bit of embarrassment, shooting her sister back a dirty look and getting a cackle in reply, but Meg shrugged and smiled when she looked at Dipper.
Pausing to glare at the interrupting sister as well, Mabel continued with the next sister, clad in blue and with her hands clasped behind her, her head ducked and occasionally meeting Dipper’s gaze with a little smile. “That’s BB, and as best as she and we can figure, she’s basically got something akin to your brain in there, brobro. All organized and lists and stuff.”
Dipper’s eyes widened, and he gave her a broader smile. BB met it, raising her head as he accepted the news with happiness rather than apprehension and disgust. Next to him, original Mabel shrugged, saying “When I found that out, we suggested she should call herself something related to Tyrone-”
Before he realized what he was doing, Dipper quickly blurted out “No,” more forcefully than he intended, and was shocked to realize he heard BB’s voice echo his own. He chuckled, rubbing his hand to his neck and grinning ruefully at his sisters, a bit unnerved when, eyes-closed in evident embarrassment, BB had done almost an identical gesture.
Sucking in a breath, purple-Mabel said “Welp, I guess that puts a firm ‘Nope’ in for that name. Moving on.”
Before she could introduce her, Indigo-Violet spoke up. “Name’s Marian, brobro.” He nodded, a bit unsure given he’d never remembered Mabel expressing interest in that name before, but she let out a sigh. “It’s from Maid Marian…from Robin Hood? You remember, when we had that play we were in for third grade?”
Dipper remembered; He was a stagehand, unwilling, but Mabel had manages to audition for and win the part of Maid Marian. Being able to help his sister helped make a job that was otherwise antithetical to his interests bearable, even fun, and years later he’d imagined what it might be like if they’d been in the play together again, as high school students, with Dipper getting the role of Robin instead of being a nameless and faceless assistant, sharing the kiss on-stage, and later when they got home, taking her upstairs while still in costume and-
Oh, right. Damn, Grunkle Ford’s mind-reader thingy is certainly thorough.
Seeing the recollection in his face, Marian pointed a finger-gun at him, saying quietly “Bingo,” as original-Mabel pointed to herself.
“And of course, you’ve got me, your original sister. Call me Mabes,” she said with a smile. “
But-” and she poked a stern finger under her brother’s nose, “-We’re all equal in this together, so no favorites, all right?” Dipper nodded, and was rewarded by his finger trailing down his chest and to the fly of his pants.
The effect on his flagging erection was immediately apparent, and his sisters closed in, surrounding him on all sides with a giggling mass of pink skin and rainbow fabric. Soon, hands were running all across him, and in short order his shirt and pants were removed, boxers following after it. Dipper helped where he could, trying to favor and play with breasts and run his hands along whichever back or thigh was within reach.
Then his attention snapped into laser-focus on the pleasure, as one of his sisters, Gabby judging from her green hairband, gently gripped his shaft, blowing on the tip of his penis before sucking gently on the head of his cock. He sighed, leaning back as a quiet happy moan escaped his lips.
She sucked there for a minute, swirling her tongue around the very edge, before removing her mouth. Dipper glanced down, and grinned, original-Mabel and Gabby both letting out a little cheer as a ring of green lipstick was visible on the end of his erection.
Other mouths soon followed, and while Mare engulfed half of his length, running her tongue back and forth under the shaft, Marian and Belle had kissed, with his cock serving as a sandwich in between. They sucked and teased the sides of his member with their tongues before pulling back, and in a stern tone, BB said “Hey, that’s cheating!”
Her protest was cut off as Belle turned to kiss her on the mouth, her hand trailing down to her thong to shift it aside and rub along the exposed mound. Marian, rolling here eyes, muttered “Fine, then,” and as Mare pulled back, revealing a smear of red, Marian replaced her, plunging to the base of Dipper’s cock. He felt fireworks bursting behind his eyes as she ran her tongue all over his cock, sucking and pulling back several times to plunge back down.
However, when she pulled back, while there was a navy-blue ring of lipstick against the base of his shaft, the other markings had been worn or sucked off, some of them entirely. Original Mabel let out a groan of distress upon seeing that, but BB shrugged.
“Normally, the parties are supposed to be competitions-” she said, ignoring when she was interrupted as Marian murmured “I won” in a stage whisper, “-But why not just give our brobro a rainbow for fun and giggles instead?”
The other Mabels nodded in agreement, especially Meg, and Belle moved back over to pleasure his erection. She had run a hand along behind him, cupping his ass, and giving it a squeeze as she sucked, running her tongue in a little zigzag as she withdrew her mouth. He shuddered, moaning, and then groaning in happiness as Mare followed her sister. Her mouth bobbed back and forth, quickly, and Dipper could feel a low tingling starting to build in his balls. He instinctively ran his hand through her hair, but evidently that keyed her to how close he was to cumming, and she pulled her head back to step aside.
Dipper’s other hand wasn’t idle, however, as after Belle had stopped sucking him, she’d instead moved to where he could reach her, and was convulsing against his hand as he ran two fingers under her, his middle finger curling into her while his thumb rubbed little gentle circles against her clit. She had one hand under a bra cup, rubbing her breast and groaning as she clenched and came, letting out a little series of happy squeaks as he drew out her climax.
May was next, sucking him, and Dipper was suddenly incredibly glad that Opti was nowhere to be found; For some reason, the idea of a pet watching as its owner gave him head seemed like it would be a great way to kill the mood, and so Dipper instead focused on how good it felt, with her fondling his balls and running a hand along his sparse chest hair as she did.
She pulled back, making a little happy “Mmm” and smacking her lips, and Meg reached down, gently massaging the unstained part of his shaft before dipping her head down. Apparently she had used some kind of warming lipgloss rather than regular lipstick, and he could feel a warm tingle where her lips met his cock. He let out a little groan, and muttered out quickly “Oh man, I’m-I’m-” as he felt the tingling of the heated lipgloss start to push his orgasm ahead of projected schedule.
Before he could say anything more, Meg moved her head quickly away, and BB came on, the little space left on the head itself where she sucked, flicking the tip of his cock with her tongue in a way that made his eyes cross, grabbing his hips with her hands to steady herself for little tiny bobs in and out, careful not to disturb the lipstick layers of another sister.
Finally, Dipper felt his shaft shudder, and BB pulled back with a moan of disappointment as Mabel put her hand on her shoulder. She quickly engulfed the tip of his cock in a kiss with her purple-painted lips, sucking as he shuddered, groaned and came. As he finished, she swallowed, and several sets of squeaking and hissed cries of pleasure came from around them. With the exception of Belle, who was sucking on her candy cane with a self-satisfied expression, most of the rest of them were rubbing themselves, including Marian.
Marian was busy running her tongue in little circles around Mare’s clit as her legs tightened around her head, Marian’s free hand teasing and pinching a nipple. As Dipper watched, Marian came, stopping her oral attentions to hunch over, her legs shaking together as her hand motions slowed. Dipper’s cock gave an appreciative final twitch, but before it could begin to go flaccid, there was a flash of light.
Startled, Dipper looked up to see Mabel had her cellphone out, and had snapped a picture of his striped cock. She giggled, showing it to him before passing it around to the interested sisters. Dipper nodded approvingly of the picture, leaning back and letting out a relaxed sigh.
Mabel grinned, giving him a wink. “If you liked this, you’ll love what we’ve got planned for the rest of this week!”
Dipper, drained of most of his energy, could do little more than make a nervously-excited “Yaaay!” He went to stretch out his leg, and accidentally kicked the chest that the Mabel Juice was sitting on.
As if in slow motion, it fell, tumbling, to crack and shatter on the floor. Purple, glittery liquid and sodden plastic dinosaurs flowed outwards, dousing the legs of Belle and May.
Dipper’s hand went to his mouth in horror, waiting for the sisters to bubble away, when May just groaned in disappointment. “Man, this is gonna take forever to wash off.” She sat back, face suddenly flush and pupils dilated. “Also, holy crap, talk about a contact high.”
His mouth went slack in confusion, as the other sisters sprang into action to clean up the spill. Mabel brought out the bag from Papyrus Dreams, specifically showing him the empty paper and ink cartons with a proud smile.
“100% guaranteed, Waterproof! Will Not Run, Bleed, Smear, Wrinkle, or Tear.”
He let out a laugh of relief, and grinned as he helped clean up the spilled juice when reality hit him:
Wait, does this mean I have 6 more twin sisters, forever?”

That night, one of the girls got up from the press of bodies to head upstairs. They had a set of blankets and thrift-store sleeping bags set up in Grunkle Ford’s old, abandoned study; Before he’d gone to bed, they’d shown Dipper, and he’d been amazed they’d been able to keep hidden so well for so long.
She snuck up the elevator, avoiding the creaking steps. Grunkle Stan had arrived back some hours after the party, but was now fast asleep downstairs. Instead, she crept over to her brother’s bed, putting a hand across his mouth to stifle the startled shriek that he tried to emit.
“Shh, shh, Dip, it’s me.”
He looked at her, bleary-eyed with sleep and confusion. He glanced over at the sleeping form of one of his other sisters; Meg had won when they’d drawn straws earlier, and was sleeping soundly in her tie-dyed shirt and green boyshorts.
His eyes widened when he realized it was not Meg, and she pointed to her purple hairband. “Original dealio, brobro. Mind if I join you?”
He nodded, wordlessly, and she snuggled under his blanket next to him. He said nothing, but she could feel his questioning look, and she sighed quietly. “Look, I…I know we said we weren’t gonna play favorites, but…you’re my brother, my brother. I love my new sisters and stuff, but at the end of the day, I don’t want to completely lose what we had, before.“
Dipper nodded, hugging her close, and she could feel his erection push upwards against her intertwined leg. She kissed the nape of his neck, saying quietly “Plus, y’know, I kinda missed not having you in me when you came tonight.”
That was enough, and with a quiet growl, he pulled her to him, shifting the thong aside and feeling around with the head of his cock. He quickly found her waiting, wet with anticipation, and with a little whimper she slid onto him.
He groaned, feeling her clench as he began to thrust upwards as she straddled him but the bed squeaked in turn. His sister put a quieting hand on his chest, looking at Meg’s still-snoring form, and instead rocked her own hips on top of him.
The sensation was heavenly, but Dipper was still on a hair trigger from all the stimulation earlier. He shuddered, clenching and thrusting upwards as he came, filling her. She groaned, running her hand to her clit and rubbing it furiously, rewarded a few seconds later by her own shaking orgasm as she humped up and down on his hips a few times as she came.
Panting, she lay against Dipper’s chest for a while, his cock going soft inside of her, and just enjoying the feeling of closeness. Then Meg snorted in her sleep, causing Dipper to murmur “You should go.”
She nodded, sadly, and climbed out and away from her brother. As she made her way down the stairs, she reveled in the feeling of his cum, dribbling into her panties, before getting on the elevator she ran her hand down to rub along the crotch of the fabric, savoring as the slickness clung to her, and she came again, bracing her free hand against the wall to avoid falling to her knees.
Forcing herself to calm her breathing,s he finally made it back to the study-turned sleeping area. Stopping by a specific sleeping form, she reclipped the purple hair bow to Mabel’s sleeping form, before making her way to her own area, and retrieving her own bow from under her makeshift pillow.
Rubbing the sodden panties, the girl sighed with satisfaction, before falling asleep.

FIN.
- 3
- 4
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Spectrum