The two siblings stared intensely at the tiny wooden door in the back of the living room. It was a pale blue color that contrasted with the rest of the brown wall. The door was just big enough to fit a small doll through, but there was no doorknob and a little silver latch held the door shut.

"Maybe if we knock, someone will open it," Mabel suggested.

"What are you two doing?" Ford leaned down to see what they were staring at.

"We're trying to open the fairy door," Mabel exclaimed.

"Fairy door?"

"Ha! Don't bother," Bill told them. He was standing by the fish tank wall that separated the living room and kitchen and was dragging his finger across the glass to lure a catfish that swam inside. "It wouldn't open for you pests. They don't like humans."

"Who's 'they'?" Dipper asked as he stood up. He grunted in annoyance as Bill seemed to be ignoring him now and didn't respond to the boy's question.

"Fairies, of course," Mabel rolled her eyes and playfully shoved her brother. "Probably."

Ford carefully watched Bill from across the room. For the past couple of days Bill really hadn't done anything to warrant much suspicion, but from what he knew of the monster there was no way he would let his guard down. Something was going on here, something bad, he just had to figure out what. Every now and then he tried to coax more out from Amy, but she would either ignore him or simply dismiss it. That girl could be so stubborn it was frustrating.

Amy peered around the corner from the kitchen and glared at Bill. "Stop teasing my fish," she said then turned to the others. "Lunch is ready."

"Finally!" Stan, who had been lounging on a recliner, stood up and stretched. "This better be a good sub to take that long."

"It would have been done sooner if you didn't request so many ridiculous add-ons," Amy retorted.

"You should've added broken glass," Bill muttered. He walked over to the front door where whimpering was coming from the outside and let in Bud whose mouth was full of mail.

The old dog entered the kitchen where everyone else was sitting at the table and promptly stood up on his hind legs and dropped the pile of mail onto the table. "Good dog," Amy said as she rummaged through her mail.

"Ooh!" A particular letter had caught Mabel's eye and she reached for the small envelope. "It's from crazy Old Man Mcgucket!"

"Mabel," Dipper scolded her as she began to open the letter. "You can't just open someone else's mail!"

"It's fine," Amy said as she looked over something else.

"Don't encourage her, Amy!"

After scanning the letter, Mabel gasped excitedly. "A party!"

Amy looked up from her pile of mail and raised an eyebrow. "Party?"

"He's having a 'hootenanny,' that's basically like a party, and the whole town's invited!" She almost climbed onto the table to show Amy the letter. "And it's tonight!" She gasped again. "We should go!"

"Eh, I'll pass," Stan grumbled between mouthfuls of food.

Amy quickly dismissed the idea. "No thanks. You guys can go, but I'd feel better staying home."

"Whaaaat?!" Mabel plopped back in her seat with a disappointed look. "But you have to come!"

"Sorry Mabel," she said. "I just don't like being around so many people. I don't even like having to go to the store." Amy stood up to bring her plate to the sink.

Mabel ran over and wrapped around Amy's leg, almost tripping her in the process. "Pleeeeeaaase! It'll be fun, come on!"

"Ah! Mabel!"

"I'll only let go if you say yes!"

"Mabel! All right! Just let go of me!"

"Yes!" Mabel jumped up and hugged her. "No take backs! Ahh!" She screamed suddenly which caused everyone to jump, including Bud who was dozing in the corner. "We have to go shopping!"

"Shopping," Amy echoed. "Why?"

"For dresses of course!"

"…dresses." Amy immediately regretted this situation. "I don't do dresses."

"And that's exactly why we need to go shopping," Mabel stated. "Come on, hurry!" She ran to the door. "Let's go now!"

"Dresses…" Amy sighed and shook her head as she slowly followed after her.

"Where are you going?" Bill asked from the living room as she passed.

"Dress shopping, apparently."

He let out a small laugh. "…Wait, seriously?"

She held her hands up and shrugged, looking mildly annoyed. "Are you coming or not? Bring the dog." She left.

"What? Hey, don't leave me alone with these guys!" He got up to follow her. "How am I supposed to obey your rule about not killing them if you leave me alone with them?" He paused briefly to hold the door open for Bud and grabbed the leash hanging from the keyholder by the door. "Hold still, mutt." He hooked the leash to Bud's collar then followed after the girls.

"This is going to be so much fun," Mabel said excitedly as she walked backwards to look at Amy.

They were walking along the sidewalk through town. Beside Amy, Bill walked with a black cane in one hand and Bud's leash in the other. It had been a long time since Amy had walked through the town; almost everyone they passed recognized her and greeted her happily. She tried to keep her greetings short as she didn't want to be asked any questions. "How have you been?" and "Are you doing alright?", two similar questions that she dreaded being asked. Like, yeah, it's been great living my whole life with no family. I'm such a happy person. Yeah, right…

Amy noticed a lot of people staring at Bill as they walked, but none of them seemed to recognize who he was. Some of them even greeted him warmly but his only responses were quick hellos and "uh-huh."

"Hey," Mabel broke Amy's train of thought. "Are you listening?"

Before she could reply, a strangely deep voice called out. "Mabel!" A large muscular girl ran up to Mabel and hugged her, lifting her off the ground. Just behind her came a smaller, Asian girl with glasses.

Mabel gasped for air after the girl let her go then smiled widely. "Grenda, Candy!"

The three girls squealed excitedly. "And I'm leaving," Bill walked ahead with the dog.

"Who's the hot guy?" Grenda asked after he left.

"Pfft," Mabel lightly slapped Grenda's arm. "Have I got a story for you two! But for now, meet Amy!" She held her arms out to gesture towards the young woman.

"Hi! I'm Grenda!"

The other girl giggled. "And my name is Candy. And you are very pretty."

"Why do people keep telling me that?" Amy looked baffled at the situation before her. "Um, nice to meet you two, I guess."

"Hey," Mabel said. "Are you girls going to the party tonight?"

"You bet we are!" Grenda shouted.

Mabel squeaked. "You two should totally come with us! We're going dress shopping."

"That sounds fun," Candy smiled.

"There's a shop right on that corner!" Grenda ran off in the direction she had indicated. Mabel and Candy dragged Amy over by her arms. Amy looked startled.

Meanwhile, Bill walked Bud further up along the sidewalk for a while until turning the corner to the next block. They paused for a bit at a crosswalk, waited for a couple of cars to pass, then continued. At the other end of the crosswalk, Bill stopped momentarily to peer down at a baby-faced boy with white hair carrying a bag of groceries.

"Can I help you?" the boy gave him an incredulous look.

"Nope. Not this time, Gideon!" He lightly tugged at the leash as he continued walking and Bud followed obediently.

Gideon tensed at the hauntingly familiar voice and stared after him. "N-No, it can't be," he muttered to himself. "Get a hold of yourself, Gideon!" He hurried away in the opposite direction, yelping as a car stopped and honked at him.

Bill led the dog back around to the other street and over to the shop that those girls had dragged Amy into. They entered and Bill dropped the leash, letting it drag along the floor as the dog followed him through the shop to look around while they waited.

Tired of waiting after twenty minutes or so, Bill began fitting Bud with a bowtie and a little bowler hat. The dog sat patiently as he tightened the red bowtie onto his collar. "Dapper dog," he said as he stood up to examine his work. Bud barked and wagged his long tail.

"Um, excuse me, sir." A worker approached them. "Animals aren't allowed in the store."

Bill turned to look at him and a wicked grin crossed his face.

"This one is perfect!" Mabel ran out from the dressing area with a bagged dress flowing behind her.

Amy followed after the three girls, relieved that she didn't have to try on any more dresses. Upon entering the main area of the store, they stopped and stared at the scene taking place. A male worker was shouting and trying to fend off what appeared to be a living wedding gown with sharp teeth sprouting from the waist and snapping angrily at the broom he was swinging at it. Amy glanced over to Bill who was lounging lazily in a chair in the corner with Bud laying at his feet. "Are you going to explain this?" she asked.

"Nope," he replied and snapped his fingers. The dress suddenly was back to normal and slowly fell to the ground in a bunch.

The terrified man was shivering in the corner and Mabel ran up to him. "We would like to buy this dress please!" She looked at Bud who was dressed up. "And those too!"

…

"I can't believe that guy just gave us this stuff," Mabel said as she held the bagged dress over her head. "Score!"

Amy opened the door and allowed Mabel to go in first. She watched her run up the stairs leaving a curious Stan and Dipper in the living room. Amy sighed as she sat down in her recliner and began to slowly rock back and forth.

"Have fun?" Dipper asked.

"Sure," she grunted.

…

"Did you hear-"

"Yes."

"Should we do something?"

"It's not our problem."

"Not yet! It will be. For everyone!"

"… What would we do?"

"…"

"Exactly."

"… Should we tell Gaia?"

"She already knows… It's not our problem."

"… okay."

…

Mabel jumped down from the last two steps of the stairs and threw her arms into the air. "Ready to party!" She was wearing a frilly pink dress that made her look like a princess; her hair was up in a bun with a cute little tiara placed atop her head and long white gloves that came to her elbows.

"Hey, not bad." Dipper complimented her as he fixed his suit.

"Not bad? Pfft, I'm rockin' this!" She grinned widely then turned to Stan. "Grunkle Stan, are you sure you don't want to come?"

"Positive," he grunted from his place on the couch.

Mabel glanced at Ford. "Aw, great uncle Ford, you're really going in your regular clothes?"

He folded his arms. "I'm only going to keep an eye on him." He shot Bill a glare.

She followed his gaze to look at Bill who was laying across Amy's recliner with one leg hanging from the side to slowly rock the chair. He seemed to be staring off into nothingness for a minute before quickly shooting her a glance. "What?" he sounded slightly annoyed.

Mabel made a face and stuck out her tongue then turned to call up the stairs. "Come on, Amy!"

They heard an exasperated sigh from the top of the stairs before Bud came trotting down in his little outfit. Not far behind him, Amy stepped lightly down the steps until she came into view. She was wearing a thin red dress that sparkled slightly as she moved; the front of the dress stopped just below her knees while the back draped down to the floor. Mabel had convinced her to wear matching red heels but Amy had insisted on leaving her auburn hair the way it was.

Both Mabel and Dipper stared at her, one excited while the other was surprised. Mabel started to squeal slightly. "You're so pretty!" Amy's only response was to roll her eyes and sigh defeatedly. Mabel noticed Bill carefully examining Amy, though his expression was unreadable. She grinned. "What do you think, Bill?"

He slowly broke his gaze away and looked at Mabel. "What?"

"Isn't she pretty?"

"Of course." He replied and turned away again. "But that's nothing new."

Amy crossed her arms. "Let's just go and get this night over with."

"Yes!" Mabel smiled but then looked a bit disheartened. "I guess we should go in Grunkle Stan's car. I mean, no offense Amy, but that old pickup truck of yours is kindaaaa… rusty."

"Oh," Amy said nonchalantly, "do you want to go in the convertible?"

"You have a convertible?" Mabel and Dipper both said.

.

The people chatting outside of the mansion gates watched in awe as a shiny cream-colored car riding low to the ground with gold trimming pulled up. Despite the nighttime darkness, every bit of the vehicle was clean and shining, even the jet-black tires. One might have assumed it was well taken care of, but the truth was that it was rarely ever used.

"Man," Dipper said as the car came to a stop. "How'd you get such a nice car?"

"It was a gift," Amy replied from the front passenger seat.

"A gift? This?!"

Bill exited the driver side and opened Amy's door before she reached for the handle. She gave him an odd look to which he grinned and extended a hand to her. She huffed and took his hand, allowing him to help her out of the car.

"Aw, don't be like that." He linked her arm in his.

"So cute," Mabel squeaked.

"What is?" Dipper asked. Mabel rolled her eyes at him then followed Bill and Amy through the gate.

Inside the old Northwest mansion, McGucket greeted each guest as they entered. "McGucket!" Dipper smiled as he approached the crazy old man.

"Howdy there! Well, if it ain't ol' Dipper and Mabel! Ya made it!" He slapped his knee and laughed. "How ya been?"

"Great!" Dipper said.

"You know Fiddleford?" Amy asked.

The old man fixed his glasses and squinted at the young woman. "Well, I'll be! Amy, that really you?" He laughed. "Well. I haven't seen you since you was just a smidge higher than my knees."

She smiled softly. "Fiddleford, you saw me last week at the market."

"Oh, I did?" He scratched his long white beard. "My memory's still kinda funny… Ah well, make yourselves at home! I got all these fancy people that keep cleaning and doing stuff for me, so don't worry if you make a mess." He purposefully knocked over a vase and it shattered as it hit the floor. Immediately, a butler cleaned up the mess and swiftly replaced the vase. "See?" He narrowed his eyes at Bill. "Say, do I know you from somewhere?"

Worrying about what Bill's response might be, Amy quickly began to walk off. Since their arms were still locked, she pulled Bill along with her until they reached the ballroom. With a smirk he turned to look at her. She turned to him, their noses almost touching, and mocked annoyance. "Don't freak out the old man. He's already crazy."

"What's the fun in that?" he flashed pearly white teeth, revealing pointed canines.

"Cute," she mocked then pulled away from him.

While Ford and McGucket began to catch up, the twins split off to find other people they knew. It did not take long for them to encounter Mabel's friends, Grenda and Candy.

"Mabel," Grenda said. "Look who we found!"

"'Sup?" A tall red-haired teen lifted her hand to greet them.

"Wendy!" Both siblings ran over to greet her.

"And –" She gestured over to a table behind her that was stacked with sweets.

"Soos!" Soos said through a mouthful of food as he stood up from the other side of the table.

"You're all here," Dipper smiled. "This is great!"

"Yup," Wendy nodded. "So? How's life in California? Give me the deets."

"Pretty boring."

"Average," Mabel added.

"But get this!" Dipper said. "Bill is back!"

She looked surprised. Behind her, Soos choked on something. "No way," Wendy said. "You're messing with us, right?"

"No, I'm serious!"

"It's true," Mabel insisted.

"Dude," Soos said. "That's uh, that's pretty bad. Right?"

Dipper took over the explanation. "Turns out we didn't really erase him. Not like we thought, anyhow. Anyways, the lady we're staying with this summer, Amy, she found him and made a deal with him!"

"What kind of deal?" Wendy asked.

"Apparently, we didn't erase him, but we did mess him up pretty badly. Most of his powers are gone, and he needed someone like her to make a deal with so he can absorb some of her powers and restore himself. Deal is, she lets him hang around and do that, and in the meantime, he'll do whatever she wants. Like a servant."

"He even had to take a weaker form," Mabel added. She pointed over at Bill and Amy on the other side of the hall. "See that really pretty lady in the red dress? That's Amy. And the guy next to her –"

Wendy gasped. "Shut – up! No way! What are you guys going to do?"

"I don't know," Dipper replied. "Ford says we should stick around to keep an eye on things. He's also been working on something in his room. I think it might be something to either trap or defeat Bill with, but he's keeping it under wraps since we're staying in the same house as the guy."

"You're living with him!?"

"I know, right! I've barely slept since we got here!"

"Why would she agree to that? Just what kind of person is this, Amy?"

Soos seemed to recognize her. "Oh, yeah. I've seen her around before. She doesn't get out much, and she mostly keeps to herself. Still, I never got a bad vibe from her. She actually always seemed kinda nice…"

"Amy's great!" Mabel smiled.

"Yeah," Dipper agreed. "She's actually really nice and cool. We don't know why she took the deal. She won't tell us. But, so far, she seems like a good person. Though, according to Bill, she's only half human. And before you ask, no, we don't have a clue what the other half is."

"So, I'm not crazy!" Someone crawled out from under the draped table.

"Gideon?"

"I knew that man I saw today sounded like Bill!" He pointed a finger in Dipper's face. "You'd better watch yourself, boy. That Cipher's nothin' but trouble and damnation!"

"Yeah," Wendy huffed. "You would know, wouldn't you?"

"Watch it, Red!" Gideon snapped at her. "You lot cause nothin' but trouble. Well, I don't want any part of it this time! Not again!" He stormed away from them.

"…What was he doing under the table?" Dipper muttered.

"Who knows," Wendy said. "But he's right that you guys need to be careful. And don't be shy about coming to us if you need help with anything. Got it?"

He smiled. "Of course!"

"Hey," Mabel said. "Why don't you guys come meet Amy? She needs to socialize more, and you guys can judge for yourselves if she seems trustworthy."

"I'd love to," Soos said. "But, uh, what about Bill?"

"Aw, don't worry about him. He follows her around everywhere but he won't hurt you guys. At least, not as long as he's under that contract with Amy. She doesn't let him hurt anyone."

Dipper rolled his eyes. "Pfft, yeah, as long as she's looking…"

"To be fair," Mabel said, "he kicked you down the stairs, yeah, but it was Flower who hurt you."

"How's that fair?! It was still his fault!"

Mabel grinned and gestured for them all to follow her as she walked across the party hall. "Are you going to stand over here all night?" She asked Amy as they neared her.

The whole time they had been there, Amy simply lingered around the drink table, avoiding conversation with people as much as she could. Bill remained silently by her side, carefully watching anyone that came close. "Probably," Amy replied.

"Well, we've got some people we want you to meet."

"Oh, goodie…"

"You don't have to be shy and antisocial with these guys. They're our friends!" Mabel held her hand out to gesture at them. "This is Soos, and Wendy. And you met Grenda and Candy earlier today. Guys, this is Amy!"

"Hey," Wendy greeted.

"Hello!" Soos smiled.

"Hello…" Amy seemed a bit bashful now. "Um, how do you all know each other?"

"We met them during our first summer in Gravity Falls," Dipper told her. "They were working at our Grunkle Stan's Mystery Shack. Soos is the owner now."

"We even have real attractions now," Soos said proudly.

"Like what?" Amy asked.

"A couple of gnomes, talking golf balls, and a creepy talking wax head. You know, simple stuff."

"Gnomes? My dog likes to chase those guys off the property. They always try to steal his dogfood. They tried to steal a chicken once, but the rooster caught them. They haven't tried that again…"

Bill was watching them all carefully from Amy's side, but he remained silent and only listened to their conversation instead of adding to it. Though, he did grin at the glare that Wendy shot him and the nervous aura that Soos was giving off. Amy seemed to notice.

"So," she said, "if you were so close back then… You must know Bill, huh?"

They seemed a bit surprised that she mentioned him to them, but they nodded. "Guy tried to kill us and take over the world," Wendy said. "Yeah, we know him." She crossed her arms and sent him another leer. "And he'll probably try to do it again, too."

"Maybe," Bill said with a shrug. "I'm not sure yet. The night's still young."

Amy shook her head a little and muttered quietly, "Not this time…"

"What do you mean?" Wendy asked.

Amy looked at her, surprised, then shook her head. "Ah, that's… Not what I meant."

She exchanged a questioning look with Dipper, who shrugged. He didn't know what Amy meant either.

"What a boring reunion," Bill said as he stepped forward. He listened to the waltz music that was beginning to play then turned back to Amy and extended his hand. "Let's have a dance."

She stared curiously at him as he smiled softly. Hesitantly, she placed her hand in his and he pulled her closer as he began to lead. Not used to ballroom dances, Amy stared down and carefully followed his movements. The soft moonlight from the windows danced on her dress which sparkled with each movement and attracted the attention of several other guests. She was much too focused on her foot movements though to notice the onlookers.

Dipper watched suspiciously while Mabel, Candy, and Grenda giggled excitedly to each other.

Amy glanced up to see Bill's eye closed, and he was quietly humming to the tune. "You act like you do this all the time," she smirked, a bit annoyed.

"It's easy." He looked at her. "You're trying too hard." Before she could retort, he spun her around, catching her off guard, and then pulled her up against his chest. She gasped in surprise and he grinned at her shocked expression. The sound of applause caught her attention and she quickly stepped back from him, embarrassed by the attention. Bill laughed and casually took her by the arm and led her back to the table.

"See?" Mabel nudged her arm. "Wasn't that fun?"

Amy grumbled something inaudible and grabbed a glass of punch. She continued to mutter until the drink reached her lips, which only amused Mabel further. The rest of the night the twins and their friends lingered around the dancefloor and Ford was off in one corner talking with McGucket about something. Every now and then the kids would check up on Amy who seemed to have relaxed a bit and was chatting with Bill. They didn't know what the two were talking about, but from time to time they'd hear or see one of the two laughing about something. Wendy and Soos seemed to conclude that Amy, although a bit difficult to read right now, did not warrant much suspicion. After watching her interact more with Dipper and Mabel throughout the night, they decided that she seemed as nice as the twins claimed. Of course, they reasonably still did not trust Bill and warned the twins to be careful and keep in touch.

"Wasn't that a fun time?" Mabel asked as they all entered Amy's car after the party had dispersed. It was well after midnight.

"Hm, yeah I had fun." Dipper agreed. "It was nice to catch up with everyone, too."

"Did you have fun, Amy?" Mabel leaned forward between the two front seats.

She thought for a moment. "Mm… Yeah, actually. I did. I still don't want to do it again. At least, not any time soon."

"Don't worry. We'll get you over your social anxiety one of these days."

"Social anxiety?" Amy looked at her. "That's not the problem! I don't like wearing a dress!"

"What? But you look so pretty! Right guys?"

"Uh, yeah," Dipper replied. "But Amy always looks pretty, Mabel."

"Indeed," Ford nodded.

Bill's only response was to reach over and push the girl back into the rear seats. "You're annoying me," he muttered after.

"Oof!" Mabel flopped back in the seat. "I've already gotten you to admit it earlier! No need to be so rude!"

"If Amy wasn't in this car, I'd put the top up and drive you guys into the lake… Or off a cliff."

"Sheesh," Amy said. "This car's expensive, you know?"

"Amy!" Dipper yelped.

"I'm only teasing!" she told him.

To be continued…

Hmmm, mysterious watchers...