Shelby tries canteening

It was Sunday evening and Shelby had just finished her paper for US History. It was 17 pages long with 40 footnotes from books she'd found at the university library across the street from her high school. She'd agonized over it all weekend and even made her brother Greg proofread it. Despite his being a smart-ass slacker he was pretty good at school stuff when **** and he'd found several grammatical errors. He'd gone over his notes with her as she kneeled in front of him and he peed into her mouth, spurt after spurt. "Shelby, you make so many comma splices. You never met an independent clause you didn't think should be thrown into another sentence." She nodded in embarrassment then he pissed some more warm urine into her wide open mouth and she drank it down, cell phone app in hand monitoring the flow.

Now she'd drank her two gallons of urine and finished her paper. She heard voices through the wall and knew Greg had a friend over. She decided to walk over in her green nightgown, even though she knew there was a fair chance they'd **** her at the minimum, and she might even get use her for some sex. This sort of thing just happened to girls and didn't have to be that big of a deal. If she wasn't okay with it happening she would just stay in her room. Now, she didn't _want _to have sex, she wasn't a slut, she was just going over to see what they were doing. If they bothered her for sex it was because they were perverts, it wasn't on her.

She walked through the tile bathroom between her room and her brother's, which made a convenient hallway to go visit Greg without her parents knowing. She walked in to see Greg and their neighbor Mike on the futon playing a bloody fighting game on the television. Shelby sat down between them casually. "Geeze why can't you guy plays something pleasant like Critter Crossroads?"

"That's a girl game," Mike said. He was a little on the chubby side and had a goofy bowl haircut. "There aren't even naked characters in it."

"Yeah cause it's a kid's game, moron," Shelby said. The game they were playing now featured lady fighters in string bikinis stabbing each other and for a finishing move, one got out a knife and fork and started eating the other! "Ewww please put on something else."

"We will if you take off your nightgown," Greg said.

"Yeah!" Mike chimed in.

Shelby sighed but stood and peeled off her silk gown. She still had on her green lacy panties as she sat back down but her large breasts were totally exposed. Still, it was exciting to be topless between two boys, especially as they'd made her do this so she wasn't being a slut.

"Nice titties!" Mike said.

"Shut up," Shelby said, elbowing him. She tossed her gown on the floor.

Greg loaded Castleweek, the super-popular cartoony shooter, and they played for a while mindlessly. The boys made dumb jokes about her boobs or her being a girl who played video games, the usual ****, she didn't really care.

When it was her turn they made her play a naked lady character, of course. Some big-boobed bimbo with a shaved twat.

"Hey Shelby do you shave your pussy?" Mike asked.

"None of your business," she said and stuck out her tongue.

Greg pushed down her panties in one rapid motion, exposing her hairless pubic mound. "Yeah she does," Greg said.

"Fuck you Greg," Shelby said, but focused on the game since she was still alive toward the end of the round, and didn't bother covering herself up. The boys looked at her twat but also watched her play and she managed to win the match.

"Hah losers, three games and the only one to get a win is the girl," she taunted them, naked now as Greg had pulled her panties down to her ankles.

"I'd say she's not a girl but the evidence is right before my eyes," Mike said crudely, looking at Shelby's bare pussy. She elbowed him again. Despite the teasing Shelby stayed naked, enjoying the chance since the boys made her get undressed, which made it okay.

"So do you have sex with her?" Mike asked Greg as he began playing his next round in the game.

"**** is gross!" Shelby protested.

"She's usually a bitch like that about it," Greg said, "But one time she was so **** for my piss she let me cum in her pussy, otherwise I was going to pee in Eleanor Landry's mouth."

Shelby blushed. "I needed my 2 liters for the day," she said defensively, "Not my fault my brother's a pervert and that Eleanor cunt follows him around wanting him to piss in her mouth."

"I can't believe our chaste class president has ****!" Mike taunted.

"Shut up!" Shelby said defensively.

"Hey I've got a full bladder, do you want it?" Mike said.

"Aww thanks," Shelby said, "But I've already had my 2 liters for the day. I don't drink it just for fun."

Mike shrugged. "Guess I'll use the porcelain urinal then," he said.

He stood up, but Shelby hated to see good urine go to waste. Tomorrow she'd really need a bladder full of piss from a big boy like Mike.

"Hey wait," she said, "This girl Wei showed me a trick called canteening. A guy pees in a girl, then there's a thing she can cork herself up with to save the pee."

Both guys looked at her wild-eyed. "You want me to pee... in you?" Mike asked.

"Yeah," Shelby blushed, "Lots of girls are doing it these days."

"I love this world!" Mike said, high-fiving Greg. Shelby blushed, but went to her room to get the GirlCork™ she'd ordered off of Nile, the home shopping mega-site.

"Well how do we do this?" Mike asked when she returned, her big boobs bouncing as she walked back to her brother's futon.

"I guess I get like this," she said, getting on the futon upside down, with her legs in the air and her head by the floor.

The boys stood behind the futon, able to see her pussy and butthole in great detail in this position, but it couldn't be helped.

"Wow Shelby you've gone from urinal to full-on toilet," Greg said.

"Shut up!"

The boys laughed.

"I guess we have to spread a hole open so we can pee into it," Mike said.

"Good thinking," Greg said, "Which one though?"

"Hmmmm let's go with her asshole, less likely to spill, I think."

"Good call," Greg said, "I don't want my futon smelling like piss."

"Use some lube at least!" Shelby protested.

"Fine, fine," Greg said, lubing his hand and fingering his sister's hairless butthole to get started. Shelby didn't ask which boy it was, it wasn't **** if you didn't know for sure that it was your brother fingering your ass. One finger became two and then three, and then an entire hand was in her butt, sliding past her anus easily. At least her brother kept high-quality lube in stock. She tried not to moan as she took her anal fisting. Why did such a nasty thing have to feel good? The anonymous hand probed her bowels, then finally pulled out and she felt fingers holding her asshole wide open.

"Oh wow I can see inside the class president!" Mike said, "Shelby I see your rectum!"

"Don't look!" Shelby snapped, "You're not supposed to see my insides!"

The boys laughed and compared her to Eleanor Landry. "I think Shelby's bowels are pinker, that's hot," Greg said.

Shelby blushed badly. "Just pee in my butt!" she yelled.

"Oh okay, let's keep it classy like the lady says," Mike said, and both boys laughed.

The boys pulled out their cocks and stood next to each other, each using two fingers to spread Shelby's butthole wide open into the ultimate anal urinal. Each started to pee, creating two simultaneous streams of amber liquid from their cocks into Shelby's rectum. They all could hear a loud splashing sound as urine began to fill Shelby's bowels.

"Mmmmm pissing into a girl is so nice," Mike said, "I'm never using a normal toilet again."

"Damn Shelby your butt can hold a lot of piss!" Greg teased.

The boys looked into Shelby's ass as the urine level rose slowly, then shook out the last drops of urine from their dick with the piss level all the way to her anus. They both leaned in to marvel at Shelby's butthole filled to the brim with pee. Mike carefully corked Shelby's ass with the specialty tool, then helped her stand back up. They heard the urine sloshing in her butt as she turned over.

Shelby stood up, feeling disoriented from having been upside down, and now from the strange feeling of her bowels filled with the boy's hot urine. It felt good, but very strange, like she had a massive insertion inside of her ass, which she essentially did.

The boys looked to each other, then down at their cocks, which were now erect.