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Smells Like Teen Spurts	By : Nastyzak Category: +G through L > Gravity Falls Views: 15483 -:- Recommendations : 0 -:- Currently Reading : 1
Disclaimer: I don't own Gravity Falls or the characters, and I don't make any money from writing.

Chapter List
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14. How to Solve a Problem Like a Mabel
Mabel had one hand up in her sweater, caressing her breasts, and the other jammed down the waistband of he skirt, fingering her pussy. Her eyes were half-closed and her lips parted and moist as she moaned, “Dipper . . . Dipperr . . . I need Dipperrr.”
“Hang on, hang on,” Wendy said. “I know what’s wrong with you. Settle down, Mabes, and we’ll help you out.”
“Want Dipper’s di-ick,” Mabel groaned. “Where’s Dipper?”
Dipper, in fact, was down in the lab, on the line to Stanford, who had returned to his home in California. “Oh, my word,” he said when Dipper gave him the news. “So there was some . . . biological material left over from the infection?”
“Some dried semen,” Dipper admitted. “And Mabel sniffed it, and then she sort of . . . went crazy.”
“The same pattern,” Stanford said. He thought a minute. “Well. First of all, I wouldn’t recommend having sexual relations with your own twin.”
“Yuck! I mean, no. I don’t feel that way about her, and ordinarily she wouldn’t, you know.”
“And the lenient marriage laws of the town do not allow for siblings to marry. All right. Um, do you know if Mabel is a hundred per cent heterosexual?”
“As far as I know,” Dipper said. “I mean, she’s never spoken about having sex with other girls.”
“But she’s spent four or five summers in the Falls and has drunk the water. I wonder . . . it might be possible to divert her urges to a same-sex partnership, temporarily. And since you are fraternal twins her genetic makeup is virtually identical to yours. Then, too, she’s in the earliest stages of infection. All right, I can recommend something, though it may be distasteful to you and her. But, in the extreme case, I suppose you could use the memory-eraser gun. I saved one model, and I can give you the combination for the weapons storage safe where I keep it.”
“Uh, that’s really extreme,” Dipper said.
“Do you think Wendy would be open to . . . satisfying Mabel for a day or two?”
“Probably,” Dipper said. “She likes Mabel.”
“Would you mind? Would it make you jealous?”
“No,” he said. “Wendy has, you know, strong bonds with Tambry and she’s okay with having sex with Pacifica. That doesn’t bother me. It wouldn’t with Mabel, either, but you know, I want to stay out of it.”
“One plus is that you are no longer creating the pheromones,” Stanford said. “Get a pad and pen and write this down exactly.”
The first stage was to sedate Mabel, if possible. “Be very careful to find the right container of tablets,” Stanford stressed. “The bottle is labeled ‘quadrazalim.’ The tablets are pale blue and round, .125 mg per tablet. Use just one and absolutely no more than two. If she’s averse to taking the pill, it will readily dissolve in wine. In that case, dissolve one tablet in one hundred milliliters of her favorite wine and persuade her to drink it. The effects will manifest in half an hour or less.”
“She’ll go to sleep?”
“No,” Stanford said. “She’ll be sort of happy and very drowsy, though. Later she’s likely to be unable to recall the events that happen within three hours of taking the dose. She will eventually fall asleep and sleep off the effects of the drug.”
“I’m not sure I like the idea,” Dipper said.
“Do you think you can deal with her without sedation?”
“With Wendy’s help, yes.”
“Very well. You may try that way. But whether she’s sedated or not, the next step is vital. Write these directions down.”
In a small freezer Stanford had placed a tray containing four ten-cc sized hypodermic needles, each with a dose of the serum. He was to find the one labeled MP. That was the variety engineered for his genetic makeup, and it should be effective in combatting the infection in Mabel.
“Can you give her the injection?” Stanford asked.
“I think so, if Wendy will hold her down,” Dipper said. “Right now Mabel gets pretty aggressive around me.”
“Then allow the hypodermic to thaw gradually. Leave it at room temperature for four hours. Keep the cap on until it’s ready for use. Then using 90% alcohol—there’s plenty in the lab medicine cabinet, and cotton swabs, too—carefully swab the skin on her buttock, left or right doesn’t matter. Plunge the needle in quickly, as if throwing a dart. Don’t let her squirm. Depress the plunger until all the serum has been injected, and bandage the injection site.”
“And that’ll clear up her symptoms?”
“Over two or three days. It should be more rapid with her because she’s recently infected and the pheromones are likely much weaker. But for the next couple of days, you’ll have to make sure that she’s sexually diverted whenever she begins to become aroused.”
“Got it,” Dipper said.
“Report back to me tomorrow. Or do you want me to fly back north?”
“We’ll try to take care of it first. Thanks, gruncle Stanford.”
He went back upstairs and tapped on the door. He could hear Mabel’s murmuring and whining. Wendy cautiously opened the door a crack. “What did he say?”
“I’ve got the shot to give her. But if she’s—”
Behind Wendy, a drowsily smiling Mabel popped up. “Dipper,” she purred. “I love you, Dipper!”
“Is she naked?” Dipper asked.
“Couldn’t keep her clothes on her.”
“My little pussy is aching, Dipper,” Mabel said. “Put your dick in me. I gotta have it, Brobro!”
“Wendy,” Dipper said desperately, “Do you think you can seduce my sister?”
“Love to,” Wendy said. “But she wants a dick.”
“I’m going to call Pacifica,” Dipper said. “You—make out with her for a little, okay?”
“You don’t—”
“Long as I’m not part of it, no, I don’t mind,” Dipper said. Mabel was trying to push past the redhead. Dipper and Wendy finally got the door shut.
Damn, it was close to midnight. Dipper phoned Pacifica. Tambry answered. “Dipper! We were just talking about you!”
“Oh, are you with—is she there in the room?”
“In the room and in the bed,” Tambry said, and Dipper heard Pacifica giggle.
“Put me on speaker.”
“Hi, Dipper!” Pacifica said in a sexy voice. “Tam and I were just talking about how much we miss you.”
“Listen,” Dipper said. “Mabel’s here. And she’s messed up.” He quickly filled them in on how there his sister had found a dried patch of his cum and how she had smelled it and how horny she was. “She’s got to have sex, she says, but incest squicks me out.”
“How’d you even know that word?” Tambry asked.
Dipper sighed. “I’m a guy. I do internet porn, okay? My gruncle Stanford says that the best thing to do is for her to have lesbian sex, so I was wondering if you two might be able to—”
“Yum!” Pacifica said. “I always thought I’d like to try on Mabel!”
“Well, bring some vibrators,” Dipper said. “Or, you know, whatever you use.”
“Double-headed dildo,” Tambry said. “We’ve got a great springy one!”
“Hey, Tambry and I used my motorized strap-on just a while ago.”
“That one!” Tambry said. “She’ll love it!”
“But she’s not bi,” Dipper said. “Uh, at least I don’t think she is. So she’ll have to be persuaded.”
“Give us five minutes to get half-dressed and packed, and we’ll jump in the car and be there in less than half an hour!” Pacifica said.
“I owe you,” Dipper said.
“And we’ll collect every drop!” Tambry replied.
Dipper went up and sat with his back to the bedroom door. He could hear the sounds from inside.
Mabel was saying, “I’ve never done this with another girl!”
And Wendy assured her, “It doesn’t mean you’re giving up guys, Mabes. It just means you want sex and another girl can give it to you. No biggie. You really are wet.”
“I want Dipper’s dick inside me.”
“I know, I know,” Wendy said. “But you’re siblings, and he’s uneasy with that—”
“I’m pretty!” Mabel insisted. “Look at my big boobies! Look at my nice, waxed pussy! Don’t you think I’m pretty?”
“You’re beautiful,” Wendy said. Here, I’ll show you.”
Then Mabel again: “Um, that—that’s nice. How—how do I taste? Ooh, could you—no, I shouldn’t—could you use your—Wendy?”
“Fingers? Yeah. You are ready for action. This feel good?”
“So good!”
Sister or not, the sounds made Dipper’s cock stiffen. He didn’t dare go inside. After some minutes, he heard a car pull up and went downstairs. Tambry and Pacifica, carrying a tote bag, came in. “Where’s Mabel?” Pacifica asked.
“Up in our old room. Wendy’s—whoa! You drove over like that?”
Pacifica had taken off her raincoat. Except for designer shoes, that garment was all she wore. “We’re decent!” Tambry said, removing her own coat. She was as naked as Tambry. “Come on, Dipper, you’ve seen everything we got.”
“He’s hard,” Pacifica said.
“Yeah, well, Wendy’s keeping Mabel distracted, and I could hear them from outside the door—”
“Come on,” Pacifica said. “I’ll help Wendy deal with Mabel, and Tambry will take care of that boner for you.”
“You owe us!” Tambry reminded him.
Pacifica didn’t even bother knocking on the door. She just barged in. Dipper got a glimpse of a nude Mabel spreadeagled on his bed, her knees drawn up, and a naked Wendy kneeling to lick her pussy.
“Pacifica!” Mabel yipped. “This isn’t what it looks like—”
“Sure it is,” the blonde said. “I know what you’re going through. Look what I’ve got for you!”
From the rear, Dipper saw her pull on what he at first thought was a thong, but as she fastened it and hip-swayed toward the bed, he saw it was in fact a strap-on dildo with a long, curved shaft and even a realistic ball sac.
Tambry whispered in his ear, “The batteries are in the balls. That’ll dazzle Mabel for a while! Let’s go to the window seat and take care of that painful hard-on you’re hiding.”
Wendy stayed with Mabel and Pacifica. Tambry undressed Dipper and pushed his dick down, letting it spring back up and giggling. “You sit on the seat and I’ll sit on your dick,” she said. “We’ll leave the door open and watch the show!”
She wriggled down, sighing with pleasure. “Still love how you fill me up,” She said. “Hey, Dipper? How about a finger in my ass? That’d make it perfect.”
As he fucked her, she dropped one hand down between his thighs to cuddle his balls. She heated up fast, starting to pump him.
Meanwhile, they could see through the open bedroom door. Wendy had stretched out beside Mabel and as Pacifica lay on top of Mabel, she pushed Mabel’s right leg back and up while Wendy held her left and reached down to tickle her clit while Pacifica fucked her.
They could hear, too: Pacifica said, “Do you like that?”
“Feels good,” Mabel groaned.
“You want it faster?”
“Yeah, faster!”
“Say you love me!”
“Pacifica,” Mabel groaned. “I’m not—uh, faster?”
“Say it, bitch!”
“Awww . . . I love you, Pacifica! Please make me cum!”
“If I do, will you eat me out?”
“Pacifica, I—”
“She’ll do it,” Wendy said. Then to Mabel she said, “I’ll show you how. You’ll love it.”
“O-okay,” Mabel said. “Please—”
Pacifica started to fuck her faster and must have turned on the vibe, because Mabel started to pump. She even nuzzled Wendy’s boob and reached to play with Pacifica’s. “Yeahh, God, that’s good!” she groaned.
“She fucks like a girl Dipper,” Tambry said to Dipper. “I gotta get me some of that. Hey, don’t cum too quick! Get that finger in, I’m getting close!”
Dipper shot his load, and then Tambry sped up as he wiggled his finger in her ass. She came quickly and hard, yelling, “Oh, fuck me, yeah!”
By then Mabel was coming. In a kind of wail, she said, “I still want to fuck Dipper!”
“Not yet,” Pacifica said, sounding stern. “First you eat my pussy! Move over, you two.” She got out of the strap-on. “Wendy, you can go. I’ll give Mabel all the lessons she needs!”
Wendy eased out, saw Tambry rising from Dipper’s dripping dick, and said, “Well, I see you two made good use of your time. Clean you up, Dip?”
“Please,” he said. Wendy and Tambry joined in to lick his dick clean, and he told Tambry about that they had to do.
“Stick the needle in her ass?” Tambry asked. “Wouldn’t you rather stick your dick in her pussy? She looks hot!”
“I can’t get around the fact that she’s my sister,” Dipper said. “Besides, I’ve got all the hot girls I can handle.”
“You’ve got a smooth tongue,” Tambry said. “Let me sit down. I want to feel it!”
It was a little weird, going down on a girl after he’d just fucked her, but Dipper had done it before with Wendy, and Wendy enjoyed it so much that while Dipper knelt, she stood on the window seat, arms braced on the sill, and bent her knees so Tambry could lick her while Dipper licked Tambry.
For the next four hours the girls took turns with Mabel, who seemed insatiable. Finally, with the syringe at room temperature, Dipper came in. Though Mabel kept saying she wanted to fuck him so bad, Wendy and Pacifica held her face-down on the bed while Tambry kept her from kicking, Dipper swabbed her right butt cheek—and if she hadn’t been his sister, he would have called it a great ass—and he darted the needle in. “This is Dipper doing this,” he said. “Hold still for me.”
“Do you love me?”
“I do if you hold still!”
“Okay. I love you. Ouch.”
She took the shot. Dipper pulled the needle out and recapped it. Wendy and Pacifica let Mabel up. She rolled onto her back, pushing her hair out of her eyes. “Dipper, please. Can I suck your dick? Jerk you off?”
“Sorry, no,” he said. “But the girls will do anything you want.”
“I want you to put your dick inside me!”
“You really don’t,” Dipper said. “You just think you do.”
Pacifica whispered in her ear.
With a sly smile, Mabel asked, “If you won’t do it with me, will you fuck Wendy while me and Pacifica and Tambry watch? And they can fuck me while you fuck Wendy.”
“Sounds good to me,” Wendy said. “But that’ll have to be later. It’s five in the morning and we’ve had like zero sleep.”
“Mabel, you and Tambry and Pacifica can have the guest room,” Dipper said. “Then when we’re rested—we’ll see.”
“Only,” Mabel said, looking puzzled, “I am so damn hungry and thirsty right now!”
“Go get a morning snack and then go to bed,” Wendy advised her.
“With Tambry and Paz?”
“I didn’t say you could call me that!” Pacifica said.
Mabel considered. “If I wore the strap-on and fucked you with it real good, then could I call you Paz?”
“Maybe,” Paz said. But she smiled and kissed Mabel right on the lips.
When the others had left, Wendy stretched and yawned. “What a night. I want to sleep until like ten. Come here and hold me.”
They got into the bed. “It smells like pussy,” Dipper observed.
“You mind that?” Wendy asked as she turned off the bedside lamp.
“Not really. Except it’s kind of disturbing that one’s Mabel’s.”
“Get used to it, man,” Wendy said. “As of tonight, your twin sister is definitely bi.”
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Smells Like Teen Spurts