I suggest you get versed in the Gravity Falls Transcendence AU before reading this. (transcendence - au dot tumblr dot com) (without the spaces). If you don't, then good luck!

"Trick or treat!"

She stood in the doorway of the home of a neighbor, smiling like there was no tomorrow. Her smile and costume (and age at that) were out of sync with the other children, who were mostly dressed in scary costumes with scary makeup, but she did not fail to put a smile on the face of everyone who passed her that night.

Her name was Mabel Pines, she was fifteen years old, and she was not too old for trick-or-treating. Her costume was simple this year (well, at least compared to other years). She wore a dark blue (she liked to call it 'night-sky colored') dress that reached just above her ankles. It was long-sleeved but cut off just a little below her shoulders and stretched across to her arms. Stitched into the dress in shiny gold thread were little stars that made the dress look like it was made up of the literal night sky.

"I'm a star," she had told her parents that night. "Oh, well… a lot of stars."

The woman holding the candy bowl smiled and dropped a few pieces of candy into Mabel's bag. Out of habit she grabbed a few more before looking at the spot next to Mabel where her brother used to stand. Where her brother should be standing. The woman's face fell slightly and she smiled sadly, remembering all the times that the Pines twins had come dressed in matching costumes, and dropped the extra pieces into Mabel's bag. "Have a nice night, dear."

Mabel smiled at the woman and skipped off to more houses for candy. She looked at her brother, who only she could see. He was floating next to her, clad in a night-sky colored suit with a gold shirt underneath. His bowtie was gold as well, and a few stars were stitched into the fabric of his suit jacket. No matter what happened, the twins would always dress alike for Halloween.

Dipper looked over and met her eyes before looking down at her bag. He was silent for a few moments. Finally, he said "I wish I could eat some."

Mabel looked down into her bag for a few seconds before snatching up a little piece of chocolate. She carefully unwrapped the candy and held it out to her brother. Dipper raised an eyebrow at her.

"Just try."

He shrugged and mumbled something under his breath before reaching out. His gloved hand closed around the candy, and his eyes widened. Mabel broke out in a huge grin and let go of the candy.

And it fell through Dipper's hand.

Dipper let out a loud yell and kicked the piece of candy that was now lying on the pavement. It went flying and hit a tree in the next yard over. He put his face in his hands. "I thought for a second that it would work."

Mabel punched Dipper in the shoulder. "Don't worry, bro-bro. You'll get it eventually."

Dipper didn't respond, and Mabel sighed. She had drawn the attention of a few trick-or-treaters that were passing by, but most didn't stop to stare. They were used to 'that crazy girl that talks to no one.'

And Mabel didn't really care. She had heard the many things said about her during her time in Piedmont after the Transcendence. She heard all those things people whispered behind her back, thinking that she wouldn't hear them. But oh she did. And she could hear them now.

"Who is she talking to?"

"Says it's her brother."

"Isn't he the one who died?"

"Oh yeah, but she doesn't seem to know that."

"Has anyone told her?"

"Mhm. She just doesn't believe them."

Mabel usually either ignored them or glared at them. Tonight she chose the latter, and the people who had been talking about her froze, realizing that she had heard, before running off, tripping over their own feet.

After watching the people run off- two boys about thirteen years old- she shot a satisfied smirk in their direction and turned back around to face her brother. She grabbed his wrist and pulled his hand down from his face. He lowered the other and glanced at her before lacing his fingers with hers. Mabel squeezed his hand, and he squeezed it back.

Mabel hit up a few more houses after that before declaring that she was exhausted and needed to make her way back home. So together they went, still hand-in-hand, back to their house. Once they arrived Mabel pulled a key out of the bottom of her pillow case of candy and stuck it into the keyhole. She opened the door slowly and quietly, hoping and praying that her parents were asleep.

But she wasn't so lucky.

"Mabel, is that you?" Anna Pines' voice drifted into the main hall from the living room. The sound of a quiet T.V. show followed.

"Yeah mom," Mabel answered, shutting the door behind her. It closed with a soft click. She hefted the near-overflowing pillow case over her shoulder and made her way to the living room.

Sure enough their mother sat, watching some talk show on the television. Mabel tried to tiptoe behind her, acting like she wasn't there even though she had said something earlier, but her mom had eyes in the back of her head. "I know you're there, Mabel."

Mabel let out a long exaggerated groan before turning to face her mother. "I'm just gonna go to bed, mom." She yawned. "See! I'm tired!"

Anna sighed. "I was just going to ask how much candy you got."

Mabel let the sack of candy slip off of her shoulder and held it up, proudly displaying her prize. This was enough candy to last her months (if she didn't eat it all at once and get sick). She gave her mother a wide smile before asking, as innocent and sweet as she could, "Can I go to bed now?"

Anna smiled back, obviously buying Mabel's little innocent display. Honestly Mabel just didn't feel like talking to anyone but Dipper at the moment. "Yes, you can go to bed."

Mabel sighed in relief and walked over to the stairs. She dragged her bag behind her. It thumped every time she climbed another step, jostling the candy inside. When she finally made it to the top she trudged over to her room: the door across from Dipper's (which, even when her parents believed Dipper to be dead, had not been cleared out or changed at all). On her door were hundreds of stickers and a little poster with a pig on it in the center. On Dipper's door hung one thing that read 'do not disturb. Probably reading.'

Maybe chuckled lightly to herself and pushed her door open. She was greeted with the light-purple walls of her room, the posters that covered them, and her demon brother, floating in the middle of the room reading.

"Took you long enough," Dipper said, not looking up from his book. He shifted to where he was floating on his stomach and the book was open in front of him.

Mabel sighed and dropped her bag. "Mom stopped me."

He looked up from his book, peaking at her with one eye. "I saw."

Mabel threw a piece of candy at him when he looked back down at his book, but it just passed right through him like he was mist. Dipper sighed and shut his book. "Don't waste your candy."

She rolled her eyes and grabbed his ankle to pull him down to her level. "Out."

He raised an eyebrow at her. "Why?"

"Because I need to get changed, bro-bro."

He raised both eyebrows this time. "Ah okay, I'll be leaving then."

Dipper awkwardly shuffled out of the room and into his own. Mabel shook her head, smiling.

Her brother was a dork.

-0-

It was two in the morning, everyone was asleep, and Dipper was extremely bored. Over the course of the past year-and-a-half he had read every book he owned, almost every book Mabel owned (he was not going to touch those romance novels, no matter how bored he was), and every book and magazine in the living room. He had even re-read half of them.

Dipper sighed and once again tried to pick up the remote on the coffee table. Just as he expected, it fell through his hands. He growled and tried again to no avail, earning another sigh out of him. He floated back over to the couch and flipped over onto his back to look up at the ceiling.

He glanced over at the T.V. Maybe if I snapped my fingers?

He snapped his fingers.

Nothing happened.

He stared up at the ceiling again. After about ten minutes of letting his mind wander he decided that he probably shouldn't do that because his mind was starting to wander into the deep, dark cave where his demon side lived and that was not a place he wanted to go.

So, once again, Dipper went to pick up the remote, expecting nothing to happen. So when his fingers actually touched the power button and the T.V. flickered to life, he nearly screamed. He jumped back and did a backflip through the air (on accident, of course) before hitting the back wall and sliding down to the floor. Rubbing his head he stood up and stared blankly at the television for a few moments before walking towards the remote, which had fallen to the floor in his panic.

He picked it up and stared at it for a long time before slowly setting it down and examining the room around him. Slowly he lowered himself to the ground and walked around on unsteady legs. Never had Dipper been more grateful for the feeling of his feet touching the carpet, or the feel of the couch as he brushed by it or even the softness of a blanket as he wrapped it around his shoulders. A bubbly laugh escaped his lips as he wrapped the blanket tighter around himself and, without trying, he floated up. Up through the ceiling and into Mabel's room.

(He never really thought too much about how he was able to still fly through walls and objects while he was corporeal. He just let it happen).

Dipper glanced at his sleeping twin and opened his mouth to wake her when he tripped over something on the floor. He hit the ground with a soft thud and nearly laughed again.

Pain is hilarious! said his demon side.

Be quiet, said his human side.

He turned back around to face the thing he had tripped over and nearly laughed again.

It was Mabel's sack of Halloween candy.

The demon reached his hand out towards the sack and hesitated.

Should I?

His hand shook a little as he thought about it before shrugging.

Well, maybe just one.

-0-

Mabel Pines woke up at precisely seven thirty in the morning and stretched. Ah yes, Halloween on a Friday was amazing. She didn't have to worry about staying out late, and she could sleep in as long as she liked (even though she woke up at seven thirty). She nearly jumped out of bed and rushed over to where her candy bag sat.

Except it wasn't there.

Mabel's eyebrows drew together and she glanced around a few times before slowly making her way out of the bedroom. Down the stairs she crept, making sure to keep quiet in fear of waking her parents. Once she reached the bottom of the staircase, Mabel tip-toed into the living room, ready for the worst.

What she was greeted with was not what she expected.

There was Dipper, her all-powerful demon brother, floating in the center of the living room having a complete candy hangover. His face was covered in chocolate, and his bow tie was undone. His jacket and hat were forgotten on the couch, his hair- which was usually styled so that it wasn't its normal curly mess- stuck up in odd places and covered his eyes, and candy wrappers littered the floor. Mabel's pillow case- which had been filled to the brim with candy the night before- was completely empty on the floor below him.

"Oh my stomach," Dipper groaned. He rolled over in the air and then clutched his stomach. "I think I'm going to hurl."

He eyeballed another piece of candy for a few seconds before picking it up and putting it in his mouth. He started coughing. "Bad idea, bad idea."

"DIPPER!" Mabel screeched before shoving a fist into her mouth to keep from laughing. She snorted loudly and all efforts to keep herself from laughing failed.

Dipper struggled to roll over to face her, and when he did his glare looked more like a pout, which only managed to make her laugh harder.

"Mabel sto-o-o-op," Dipper complained. "This isn't funny!"

"Oh it so is!" Mabel laughed again, and Dipper's glare increased.

He opened his mouth to reply, but it seemed like every word died on his lips as his expression changed to one of indifference and his gaze shifted to a point behind Mabel. Mabel's eyebrows drew together in confusion. Usually her brother had some witty retort or something. He didn't just stop. "Are you okay, bro?"

He didn't reply to her, just said "Oh hello, mom. Dad." He nodded to two different spots behind Mabel, and she slowly turned around to face her parents.

There they stood, still in their pajamas and their hair a mess, eyes wide and mouths open. In her father's hand was a sharp knife from the kitchen- the one that the twins' parents had warned them to never touch when they were little.

Mabel glanced back at her brother, who was re-tying his bow tie. After he finished he waved his hand, and a little handkerchief appeared. He used it to wipe his face before it disappeared again.

Dipper gestured towards Mark's hand, and then to Anna's. "I see you've come prepared."

His drew his hand back to his side, and he let out a shaky breath, obviously trying to calm himself. "I also see that you thought I hurt Mabel." His voice cracked a bit, and he closed his eyes. "You actually thought that I hurt her."

Mark and Anna glanced at each other before turning slowly backing out of the room. Mabel took Dipper's hand and shot a glare at where her parents ran off to. This was the final straw. She had tried so hard to keep a smile on every time her parents shied away from Dipper or acted like he wasn't there, but this was it.

When the twins finally moved to Gravity Falls, they remembered what happened that morning.

And they never really forgot.