The yellow triangle guy Bill Cipher was pretty bored, so he decided to swap the minds of two random people in Gravity Falls for a day as a way to entertain himself.

"Alright, now let's see who my two victims will be," Bill smirked to himself as he snapped his fingers.

He then looked through the mindscape to see whose minds he had swapped and saw Pacifica Northwest on one side and Mabel's adorable pet pig, Waddles on the other. They were both asleep.

Bill's one eye widened. "Wow! I swapped the minds of a girl and a pig?!"

He laughed wickedly. "Aw, man! That's amazing! Oh! I can't wait to see this train wreck! Oh, let me get a glass of juice…"

He got a glass filled with grape juice, then headed back to the mindscape and waited excitedly with an evil look for Pacifica Northwest and Waddles to wake up so that he could see his disaster he had set up for them.

Pacifica had just woken up. She yawned and was about to use her hand to push herself up when she noticed that her hand wasn't a hand!

"AHHHHHHHHHHHHHHHHHHHHHHHHHHH!" she screamed, staring at her transformed hand. She saw that it looked exactly like a pig's hoof. "Why the heck does my hand look like a pig's hoof?...OMG! Am I a...a.. pig?!" she wondered aloud. She was about to scream for her parents for help, when she noticed that she wasn't even in her own room! She was in Dipper and Mabel's room, with Mabel right next to her, squeezing her in her arms with a hug smile in her face.

Pacifica's eyes widened in horror and she was about to scream again, but then stopped. "Wait… maybe this is all just a dream," she said, looking a bit relieved. "I'm probably still sleeping. I bet when I wake up, I'll be in my bedroom in my body and everything will be normal!"

She closed her eyes. She even pinched herself a couple of times to make sure she was dreaming. But nothing changed. When she opened her eyes, she saw that she was still in Dipper and Mabel's room, right next to Mabel. She caught a glimpse of herself as a pig in a nearby mirror.

"OMG!" Pacifica went into a full blown meltdown. "I REALLY AM A PIG AND I AM IN DIPPER AND MABEL'S ROOM! THIS IS ALL REAL!"

Mabel eventually woke up and turned to look at her pig with a grin, not knowing that it was Pacifica. "Good morning, Waddles!" she chirped cheerfully. She soon noticed the panicked look on her pig's face and she grew concerned. "Waddles? Are you okay? Why do you look so worried?" she asked in a worried tone.

"Waddles? Who would name a dumb animal Waddles? Oh, that's right. Mabel would." Pacifica muttered softly to herself.

Mabel looked at her pig worryingly for a moment, but then burst into a big smile. "Oh! I know what's wrong! You are probably just scared about the day when I have to leave you behind when I have to go back home when the summer's over and you don't wanna be alone."

Pacifica wasn't focused on what Mabel was saying. All she could think about was how to get out of here and get back into her own body.

"Well don't worry Waddles! I swear that I will convince my parents to let me keep you! I won't stop till they say yes! And when they do, you and I can be together forever!" She pulled her pig in for a hug.

Together forever? If there was already hated being a pig, but she even more hated spending another second with Mabel.

She broke free from Mabel's hug and ran out the door.

"Waddles!" Mabel gasped. "Wait! Come back!" She ran after her pig. "Wait! Where are you going?"

Pacifica noticed Mabel running up towards her and ran as fast as her little pig legs could carry her to escape her. She didn't want to spend another second with Mabel. She had to find a way to get out of the shack fast and figure out a way to get her old body back.

Waddles had just woken up in Pacifica's room at the Northwest Mansion. He gave a little piggish snort and climbed out of bed, walking around like a zombie. He grew curious about his new surroundings and couldn't resist touching the new stuff he saw around the room. He knocked down perfumes and makeup kits and soon completely trashed Pacifica's room. He even started eating her designer shirts.

Suddenly, Pacifica's mother and father entered the room. "Pacifica, darling, can you come here for a minute?" Mr. Northwest called out to her.

Waddles turned his head toward them, looking at them cross-eyed. He walked in the zombie way toward them.

Mr. and Mrs. Northwest looked at each other nervously before Mrs. Northwest began talking. "Look. We know you are not going to like this, but we have to inform you- due to us needing to save money for a big party we are hosting later on…., we're afraid we're going to have to buy you one pony."

They looked at Pacifica nervously, waiting for her to have a nervous breakdown and yell at them.

Waddles stared at them, cross-eyed for a moment. Then he grabbed Mr. Northwest leg and started chewing on his pant leg.

"AH! PACIFICA!" Mr. Northwest screamed. "WHAT HAS GOTTEN INTO YOU?!"

"This must be her new way of touchering us because we're not going to buy her more ponies!" Mrs. Northwest cried.

Mr. Northwest pulled his daughter off his pant leg and then placed her on the ground. "Alright, Pacifica, we'll buy you another pony, I promise!" He told her. "Just don't do that thing ever again!"

He and Mrs. Northwest nervously watched their daughter as they exited the room.

Waddles watched them go and as soon as he was gone, he began chewing on Pacifica's designer shirts again.

Bill cackled to himself all the way since they had woken up while he was watching this. "Oh, this is amazing! This is one of the greatest things I have ever done so far! Oh, I'm not gonna switch these two back anytime soon!"

And so Waddles was stuck as Pacifica and Pacifica was stuck as Waddles.

For now, they would be stuck in each other bodies.

Little did they know, that each of them were going to have a big adventure while they were in each other's bodies.