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The Bikini	By : Cocotheblueperv Category: +G through L > Gravity Falls Views: 12988 -:- Recommendations : 0 -:- Currently Reading : 0
Disclaimer: I do not own Gravity Falls or any of it's cheracters. And make no money off of this story

Chapter List
- 1-Innocence Given
- 1
Chapter 1: Innocence Given
We open to twelve year old Mabel Pines running through the forest chasing after butterflies, her signature sweatshirt flowing in the breeze as she laughs manically. With one misplaced step she trips over a previously unseen object. “Gah!” she yells before she lands face first in a mud puddle left over from the rain the night before. She stands wiping the mud from her face before looking for whatever she tripped over, her eyes widening a she catches what it was. A small wooden chest, the rounded top just barely sticking out of the mud. “Wha-“she exclaims kneeling down, as her curiosity takes over, to dig it out. With the chest freed from its earthy prison Mabel quickly opens it, discovering that it is unlocked, her eyes go wide at the sight of its contents.
We find Dipper sweeping the floor in the Mystery Shack until the door slams open, his older twin sister Mabel standing in the door way covered in mud and clutching a filthy chest. “Mabel I just cleaned there!” He yells throwing the broom to the floor.
“Forget that Dipper, you have to see what I found!” She exclaims giving him only time to raise his eyebrow in curiosity before taking his hand and dragging him up the stairs to their room.
“Okay wait here I’ll be back.” She orders before turning with chest in hand and making her way out of the room.
Dipper kicks his legs impatiently on the bed for what seems like hours, despite being less than five minutes before Mabel steps back into the room the two share exclaiming “Tada!”, his eyes shoot open and his mouth hangs agape at the sight before him, his sister wearing a tight fitting sequin bikini.
“Mabel what are you wearing?!” He nearly finds himself shouting.
“You like it? I found it in that chest in the woods.” She spins giving her brother a full view, the tight fabric of the bikini bottoms clinging to every curve of her rear.
“Y-you shouldn’t be wearing that, especially if you just found it lying around!” Dipper yells while turning his head to the side as a light blush crosses his face.
“Aww, but it’s so cute and sparkly!” Mable says nearly singing as she twirls around again, the sequins shining in the lit room.
“You have no idea where it’s been! For all we know it could have been McGucket’s or something!”
“Blah!” Mabel sticks her tongue out in disgust. “It’s coming off.” She says as she rushes and throws the top off revealing her bright pink nipples topping her barely noticeable breasts immediately before reaching down and starting to pull down the bottoms.
“M-Mabel, not here!” Dipper exclaims, his cheeks turning bright red.
“Why? It’s not like we didn’t used to take baths together.” Mabel states matter of fact.
“I know, I know, but we were kids!”
“We’re still practically still kids now!” Mabel throws up her arms, her bikini bottoms sliding down to her feet revealing her bald cleft.
“Mabel, I mean, we were . . . um,” Dipper stutters trying to explain it without sounding too weird, “we weren’t . . . developing . . . then.”
“Developing?” Mabel asks stepping out of the bikini bottoms and walking towards her brother, clearly not having had the same talk he did with their father. “Whatcha’ mean by that?”
“Y-you know, I mean, like growing, in places and al that . . . stuff.” Dipper steps back continuing to avert his eyes from his sister’s blatant nudity.
“Oh? So you’re growing eh?” Mabel says slyly as she ducks down and rips his pants and underwear to his ankles.
“Mabel!” He yells before jumping back onto his bed and wrapping himself in a blanket with only his head peeking out, leaving his pants and underwear behind.
“Oh come on! You got to see me naked,” she motions with her hands towards her bald prepubescent cleft.
“It’s, It’s not like I wanted to.” Dipper stutters unsure of how to react.
“It’s not fair!” Mabel pouts at him, stomping her right foot against the wooden floor.
Dipper sighs and pulls the blanket down to his waist freeing his upper body and quickly throws his vest and shirt off, hesitantly looking down at the blanket before closing his eyes opening it, his little soldier standing half at attention.
Mabel grins widely and crawls up onto the bed, and crouches, her legs apart, unknowingly giving her brother a clear view of her young pussy.
“Okay, so now we’ve seen each other naked.” Dipper says shaking the vision of his sister’s hairless coochee and starts to wrap himself back up in the blanket.
“Nuh uh! I want a better look!” Mabel says as she leans forward and looks closely at Dipper’s one eyed snake, it twitching with anticipation as he feels her breath. “It moved!” she exclaims poking the pink tip of his penis lightly making him let out a soft moan before she starts to run her finger along its length as it slowly hardens. “Hey does it feel good?”
“V-very, but th-this hay to sto-“ He start to say but is cut off by a soft moan.
“Why? If it feels good it has to be good.” She says taking his growing member in her hand and softly starts stroking it. Dipper moans out as he feels his member taking in his sister’s grasp, his protests rendered mute as he gives in to the pleasure/

“K-Keep doing that.” He moans out in between breaths as precum seeps from the tip of his cock.
Mabel curiously leans in and softly gives the tip of her brother’s cock a testing lick, the salty fluid coating her tongue before she wraps the tip between her lips, sucking softly as her tongue dances around it.
Dipper moans out and lays back as he start to pant, his cock throbbing at full mast as his sister starts to bob down the shaft slowly taking more and more of its length with each movement. Dipper moans her name softly, her hand trailing down her stomach and resting between her legs. With the first touch of her moist slit she moans around her brother’s shaft as she experiences her first taste of pleasure, her brother looks down at her and notices her hand before pushing her off his throbbing member not wanting to cum so soon, his breathing labored.
“Time to return the favor.” He lays her back and moves between her legs starting at her thigh and kissing up to her dripping honey pot, a soft blush on his face as he inches closer and closer to his sister’s forbidden tunnel.
“Dipper.” She moans out, instinctively spreading her legs for her forbidden lover. She gasps in pleasure as he presses his lips against her dripping cleft before running his tongue through her valley causing her to shudder, her toes curling into the blanket as her moans get louder and louder with each lick. “Oh, Dipper it feels so good!” she moans out.
“Then you’ll love this.” He says before he starts flicking his tongue softly over his sister’s clitoris, she shudders as pleasure flows through her body like a bolt of lightning. As his sister nears her peak he stops just shy of pushing her over the edge.

“D-Dip-mph” she is cut off as he shoots up her body and kisses her, his tongue shooting into her mouth as it dances around hers she moans into his before he pulls back, a trail of saliva hanging between their lips. “I taste good.” She pants out having savored her taste on his tongue. She reaches down and spreads her lower lips, exposing her glistening pink inside. “Dipper, let’s feel good together.” He nods and prods his throbbing member against her untouched hole and slowly pushes forward until the opening gives way and the head of his cock is engulfed by her impossibly pussy.
She gasps out as she is penetrated by her brother, “Oh God Dipper, it so big!”
He grunts tries in vain to push forward, “Y-your just too tight.” He moans out.
She moans out “Please Dipper, I need more my kitty is on fire!” She wraps her legs around his hips and pulls tightly, wincing, her eyes closed tightly as she forces her brother to take her maidenhood.
Dipper moans out as the entirety of his cock is consumed by his sister’s “kitty.” “Mabel are you okay?”
She opens one eye still adjusting, “P-Please go on, I want you to feel good.” He nods and slowly pulls back, leaving just the tip in before slowly thrusting his length back into her.
“It’s so good Mabel!” he moans out as his thrusts pick up speed and his sister’s expression changes, her lips hanging open as she moans louder and louder with each thrust. His thrusts turn to a blur as he loses himself in the passion, he leans forward and kisses his sister again, their moans muffled as their tongues dance and explore each other’s mouths until Mabel pulls back.
“Oh God, s-somethings coming!” she moans out, her legs clamping tightly around her brother’s waist as she moans, “Oh God, oh God, oh God . . . “ Her pussy walls convulsing around the intruding shaft as her juices are forced around it.

“I-I feel it too!” Dipper moans out as he thrusts one last time, his white hot cum shooting into his sister’s young womb before collapsing on top of her.

“That . . . Was . . . Amazing.” Mabel pants out as she lets go of her brother, her legs falling to his sides.

“Y-Yeah, oh wow.” He pants as he rolls to his side, his softening cock pulling from his sister’s confines. “Hey, Mabel?”

“Yeah? “ she turns looking at him as their combined juices leak from her.

“Will you be my summer romance?” he smiles nervously chuckling a little.

“Only if you be my everyday romance.” She leans in to kiss him.

“Of course, Mabel. Always.” He leans in and kisses her, their tongues dancing around one another.
To be continued . . .

I hope you enjoyed my first fanfic ever. Please comment with any tips, suggestions, or praise. There is much more to cum. On a second note the anal tag is for future chapters I am working on.
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The Bikini