I wrote this shit as a bet so

don't expect a literary masterpiece

Dipper had just seen Wendy in a bathing suit because she was going to the pool with her friends, so of course with his pent up preteen hormones he had to beat one out in the safety of his room. Unfortunately for him Mabel was traipsing up the stairs, Waddles in tow.

"Dipper! I- what the heck?!" Mabel immediately stopped in her tracks at the sight of her brother hunched over, shrimpy dick in hand.

"Mabel, I- it- it isn't what it looks like!" Dipper tried to zip up his fly but was halted by the advances of his twin sister, who got on her knees and starting poking it in a morbid curiosity. "Mabel, stoooooop," Dipper groaned in a voice that betrayed his true thoughts.

"It's so weird... is it always like this?" Mabel asked, inquisitiveness seeping through her tone. "Huh, it's kinda... cute," she said, as she began to rub her thighs together and bite her lip.

"Mabel! Don't say that!" Dipper looked affronted. "Can you please leave now so I can try and regain at least some of my lost dignity?"

Mabel cocked her head to one side, then the other, making a "Hmm" sound as she did. Then she got up, and walked away...

...only to grab Waddles and slam him directly onto Dipper's schlong.

"Hnng!" The boy clearly was not expecting such a turn in events. "What the hell, Mabel?"

"GRUNKLE STAN! GET UP HERE!" Mabel exclaimed. "YOU'RE GONNA WANNA SEE THIS!"

Her twin panicked and tried to pry the pig off his disco stick, but Waddles' ass was too tight. "Mabel, please, why are you-"

Dipper's protests were cut short by the appearance of their beloved Great Uncle Stan. As Stan stood in the doorway, the two had an intense stare down that seemed to last an eternity.

"I see why you brought me here, Mabel." Grunkle Stan, clad in boxers and a wife beater, reached into his pants and started caressing his wrinkly dick at the same time that Mabel started to feel herself. "Now, Dipper, I ain't as young as I used to be, so I'm only gonna say this once- fuck the pig."

Dipper looked aghast. "What?! Grunkle Stan, I-"

"Fuck the pig, Dipper!"

The boy in question swallowed hard, taking note of the fact that his member was still enlarged. He supposed a pig's ass didn't feel too bad, or different from a human's- not that he'd know. Without another word, he began to slide Waddles up and down on his rock hard meat stick.

The pig began squealing as Dipper's dipper slid in and out of his puckered asshole. All that did was motivate everyone in the room to do what they were doing faster- it soon became a cacophony of moans as everyone pleasures themselves in some way.

"Alright, kid, I'm coming over." Stan took a bottle of lube out of seemingly nowhere and rubbed it all over his girthy white cock. "Brace yourself, Dipper."

Dipper only nodded and kept fucking Waddles as Stan walked over to him and slid his pants off of him. Then, spreading his ass wide, Stan slid into Dipper with one motion and a load groan. Mabel continued to touch herself in the corner.

Dipper was entranced by the sensations he was experiencing. His dick was in a pig, his Grunkle's dick was in him, and his twin sister was moaning loudly and touching herself in the corner of the room. It was too much for his pre-teenage body to handle.

"Grunkle Stan, I think I'm almost there!~" he exclaimed, knowing he was reaching his limit.

Stan grunted. He was getting close, too, and would probably reach his climax before the boy, especially due to his older age.

Mabel got down in front of Waddles, and started feeling the pig's dick as she continued to touch herself. The normally talkative girl couldn't say a word, enraptured within the throes of pleasure as she was.

With one final groan of pleasure, Grunkle Stan orgasmed, and the feeling of his Grunkle's warm and sticky seed inside his ass was too much for Dipper, and he unloaded inside the Pines' pet pig. Waddles himself squealed as he came all over Mabel, who quivered as the scene unfolding in front of her caused her to climax.

The Pines family, all spent, collapsed on the ground in heaps. Grunkle Stan pulled Dipper, Mabel, and Waddles close to him, sweaty and dripping in bodily fluids as they were.

"I think that's good family bonding, dontcha think, kids?" With that, they all fell asleep.

"Uh... dudes?"

what the fuck was I thinking