Hey there everyone! I posted this originally on AO3, and after completing NaNoWriMo last month I decided that I'd also put it up on here. This fic will be BillDip, so I don't advise reading if it's not your cup of tea ^-^

"Ladies and gentlemen!" an overexcited voice called into a microphone at the front of the stage. "I'm proud to present the Piedmont High School class of 2018!"

Mabel Pines smiled brightly with brace-free, pristine white teeth at the audience before continuing her speech. "Before we go on to the more fun stuff, I'd like to read a little something for you guys that I literally wrote last night!"

From his spot beside the other graduates and the empty chair that belonged to his twin, Dipper smiled at her enthusiasm. How she'd managed to pull the spot of valedictorian, he'd never know. His eyes briefly caught hers and he smiled wider and gave her a thumbs up.

She cleared her throat, then began the poem that she'd recited about a million times in front of the mirror the night before.

"Farewell to my greatest comrades –

The years have been many, and the struggle long.

The wise ones still doubt we'll go very far –

But that's okay, I promise we'll prove them wrong.

As you go on into the unknown,

A piece of advice to carry you home –

Love comes and goes, it dies and we grow.

There's uncertainty around every corner,

And demons to make you falter.

Never forget though –

No matter how you think it,

You're never alone."

Applause rang out as Mabel finished her speech, but quickly died when she pulled out a device that strongly resembled a mix between a gun and a cannon.

Dipper knew better though, and his grin was the only one that remained as she pulled the trigger back.

"Confetti time!" She screamed, releasing. A large burst of confetti shot from the cannon and scattered over the crowd. "Thank you Piedmont!"

She flounced quickly back to her seat, her smile about a mile wide at that point. The audience clapped again, though less enthusiastic than before.

The ceremony went on, and finally came the time for names to be called and students to receive their diplomas.

Dipper relaxed in his seat and lightly closed his eyes, knowing that Mabel was far too high from Mabel Juice to let him completely let him fall asleep.

Surely enough, it seemed like only a few seconds had passed before Mabel was gently shaking his arm. "Dipper," she whispered as he blinked his eyes open. "Our row is next."

"Thanks," he mumbled back, shaking his head slightly to ease the sleep from it and sitting up straighter.

Only a moment more passed before his entire row stood and filed over to the steps leading onto the stage, his luck making him the first to go.

"Dipper Pines!" His name was called over the microphone and he took a jolting step forward in response, everything suddenly feeling like a dream.

Time slowed as he stepped forward and seemed to stop as he shook his principal's hand and murmured a thank you.

He looked over to the crowd and quickly found the section his parents were seated in. They were next to Grunkle Stan and Grandpa Stanley, and between the two older twins sat a guy around his age with a wide smile on his young face.

The teen had scruffy blonde hair that covered one eye, and the other was a cerulean color, the brightest blue he'd ever seen on a male.

He smirked and quickly blinked when he caught Dipper's eye, though he could have sworn that he had winked at him.

Time sped up again, and he looked back at his principal and gave him one last nod, then walked off in time to hear his sister's name get called. A few moments passed and a resounding whoop from his twin echoed around the auditorium as he took his seat.

Mabel joined him quickly, her face slightly flushed from the pure excitement and energy that he was sure was coursing through her system.

"We did it Bro Bro!" she whisper-yelled enthusiastically, shaking him a little. "Wasn't my speech badass? And the confetti? They loved me! Best valedictorian speech ever given!"

"It was," he agreed hollowly, glancing back toward where his family was seated, noting that the mysterious teen was gone. Had that all been in his head? Who was he?

He looked back at Mabel to see that she was frowning and gave her a small smile in reconciliation. "Sorry, I thought I saw something funny when I was on the stage."

"Ooh! Like what?" Mabel asked, scooting her chair closer to his so they could talk quieter.

"It was just some guy," he replied despondently, brushing off the incident. "He looked like he was sitting with Grandpa Stanley and Grunkle Stan though, which is why it was so weird."

His twin giggled quietly, "you dummy! They brought somebody with them because he really wanted to see us graduate! When I talked to Grunkle Stan, he wouldn't tell me much besides the fact that the kid's been staying and working at the shack since the beginning of the year."

"Did you catch a name?" he asked her curiously, glancing over at the audience again.

She shook her head, "no, but we'll be properly introduced to him on the way to Gravity Falls. I'm so excited to go back!"

The last of the graduates filed over to their spots, and a moment later the rest of the class stood on their cue. Dipper felt a small rush of excitement wash over him as he finally realized that this was it. After the next half hour, he would no longer have to get up for school ever again, that after today he would be officially recognized as an adult.

"Class of 2018," the principal began solemnly, though there was a smile on his face. "This is the last act you will perform as Piedmont High students, and these are the last instructions you'll receive from me."

"The turning of the tassels symbolizes one's transition from candidate to graduate. And in this act, you are taking an oath to yourself and to your community. The oath states as follows: We vow never to disgrace our city or ourselves by being cowardly and dishonest. We will continue to strive toward the sacred ideals that we hold dear. We will respect and obey the city's laws and we will do our best to inspire others to do the same. In all these ways, we create a better, brighter place for ourselves, and for those who will come after us. I would now like to ask the graduating class of 2018 to turn your tassels from right to left."

Mabel and Dipper switched their tassels at the exact same time. As they caught one another's eye they quickly fistbumped and tossed their caps into the air, much like their classmates were. The audience cheered enthusiastically and some of the more outgoing seniors, Mabel included, whistled back to them.

It took a while for the crowd to begin dispersing and for the twins to make their way over to their family. The blond-haired teen was back, Dipper noticed, and he was wearing his seemingly ever-present smirk again.

"Dipper Pines!" the teen exclaimed in a voice that was oddly high for a male his age. "It's great to finally meet you!" He held out a hand and Dipper hesitantly took it.

It was like something electric, the sensation Dipper got from holding his hand. He found that, like with the male's voice, he didn't completely mind.

"I'm Dipper," he started awkwardly, "but you already knew that."

"I just couldn't believe my ears when I heard that you'd be coming to stay at the shack for the summer!" The teen continued enigmatically. "I thought to myself – finally! Another interesting person to roam the woods with!"

"Yeah…" he let the thought trail off, finally letting go of the teen's hand. "Look, I'm sorry, but who are you?"

The question didn't deter him, rather, his smile grew wider. "My name's William!" Your great uncle hired me to work for him a while back and told me that I could stay in the shack. I was thinking that we'd be roommates for the summer, but Stanley said that you and Mabel are used to sharing. It's not the biggest problem though, I just kinda built my own home at the edge of the woods."

"It's nice to meet you," Dipper replied cordially, thinking. It'd been a year since he and Mabel had last shared a room, and he wasn't even sure that she would want to this year.

Thinking of his twin…where was she anyway? He looked around and found her chattering animatedly to Grunkle Stan. She pulled out the confetti cannon that she'd with and modified last summer, and he laughed heartily and ruffled her hair.

"She's quite a gal," William said quietly from his place beside Dipper. "Are you going to miss her when she goes to ULA?"

He nodded. "Of course, but…" he hesitated. Did he really want to completely reveal a secret of Mabel's to a guy he'd only just met? He settled for a half-truth and continued. "A friend of hers is going too, and Mabel worked really hard to get in. I'm too happy for her to really be very upset."

"It makes sense," William mused, nodding slowly. "And what about you? What college will you be attending?"

He laughed nervously, scratching the back of his neck. "Well…"

"Dipper hasn't decided yet!" Mabel interjected, appearing seemingly from out of nowhere. "Have you Bro Bro?"

He shot her a grateful smile and shook his head. In reality, that was half the reason he was going to Gravity Falls in the first place.

"Hello," William said politely to Mabel, his grin wide again. "That was some speech you made there."

"Thanks!" Mabel beamed at him, smiling back brightly. "It's great to meet you William!"

"The same to you!" he replied enthusiastically. "I heard that you have a knack for making some pretty fancy sweaters and it tends to get pretty cold in the winter. Do you think you can make me a few?"

She nodded quickly, her eyes lighting up with more euphoria than she'd had all week. "Of course! I'll make you one for every cold day of the year!"

"Oh," he laughed in an almost awkward fashion, rubbing the back of his neck sheepishly much like Dipper had. "That won't be nece-"

"Nonsense!" Mabel cut in, waving her hand dismissively. "It won't be a problem and besides – we can't have you wearing a single sweater twice within the same year span!"

"Don't try to defy her," Dipper warned, a slight smirk crossing his lips. "It won't end very well." With that being said, he walked over to the rest of his family, allowing Mabel some time to brainstorm sweater ideas with William.

"…And as hard as it is to say this, I'm actually kinda proud of him," Grunkle Stan was saying to his parents. "He'll be useful when it comes to running the shop this summer."

Even though his parents were proud of him graduating with honors and all, his Grunkle's plan to teach him how to run the shop was frowned upon and had often been the subject of many late night arguments over the last year.

"He probably won't be able to stay very long," his father pointed out, half scowling. "Freshman orientation for Harvard starts pretty early into the summer."

"Actually, I'd love to run the shack," Dipper input as he walked up to them. "So long as I get a pay raise, it'll be a good use of time."

"You'll miss orientation," his father reiterated through gritted teeth.

"That's for summer classes," he retaliated, shooting his father a small glare. "Fall class orientation doesn't start until the end of July."

"We should start heading out to Dustee's," his mom cut in, checking her watch. "Our reservations are at 7:30 and their management doesn't tolerate lateness."

Dipper sighed, "I'll go get Mabel…"

He turned to go fetch them but to his surprise, they were already headed over, Mabel grinning excitedly and William gazing down at her with something that looked akin to affection in his eyes.

"Did the sweater planning go that well?" he asked skeptically the second she was within hearing range. She glanced at William mysteriously then nodded her head, her smile widening.

"Awesome," he muttered under his breath, glancing at the duo. Mabel had already confided in Dipper about her feelings for Pacifica Northwest a long time ago, so what was she playing at? Unless it would spin off into some sort of attempt to make the rich girl jealous, it seemed like she was going back to her old boy crazy habits.

"Mabel here was just telling me about your old crush on that red-headed cashier girl," William teased, blinking as rapidly as he had done earlier. This time, he was sure that it was a wink.

He flushed and looked down, embarrassed that the Wendy subject had been brought up to the stranger so quickly. "Yeah," he mumbled. "I'm over it though."

Way over it, he thought hollowly, thinking of the last time he'd seen Wendy – they hadn't been on the best of terms. He hated fighting with her, but the mysteries of Gravity Falls were too important for him to just let it go. Obsessed, she'd snapped at him before storming out of the shack.

He shook the memory away at the sensation of a tugging on his graduation robe's sleeve. Mabel had gone over to the rest of the family already, leaving William to stare at him curiously.

"Something wrong?" the blond asked in a concerned tone.

"It's nothing," he murmured, shrugging off the question and walking over to where the rest of the family was. "Just an old memory."

Luckily for him, the teen didn't say anything else.

"This is a pretty nice place you've got here!" William commented as the remainder of the Pines family pulled into the driveway of their gated-community home. "I didn't think that reserved people such as yourselves lived in such luxury!"

"It took a long time for us to be able to have this," Dipper told him as he undid his seatbelt and stepped out of the car that he shared with Mabel and the blond-haired teen.

Their parents were already home, and both Stans wanted to set off to Gravity Falls as quickly as possible. William would be staying at the Pines residence for the night so he could accompany them on the journey over to Gravity Falls.

"You should have seen the trailer we were living in before," Mabel added, stepping out of her spot in the backseat. "Dad got seriously promoted in his job the first summer we went to Gravity Falls and he had this place built while we were gone."

"So that's how everything started," William mused, glancing up at the sky intently. "And you guys just kept going back? You cared about the mysteries that much?"

"You know about that?" Dipper asked him suddenly in a quiet tone, stopping in his tracks and staring unashamedly at him.

William looked down and over to him, smiling widely. "I live in Gravity Falls," he pointed out. "A person would have to be stupid not to know! Plus, my knowledge of the supernatural has really helped out with the Mystery Tours and everything."

"It makes sense," Mabel remarked. "Plus, with Stanley's immense paranormal knowledge and paranoia, he probably educated Will on the subject when he started the job."

"Will?" Dipper asked, unimpressed, an odd notion clicking in his mind.

"It's a nickname I assigned to him," she told him, bounding up the steps and into the Pines residence. "Short for William." Dipper shrugged and followed his twin, the aforementioned blond trailing just slightly behind him.

The front hallway of the home was painted a simple cream color and had pristine creamy tiles to match. There was a shelf with a few trinkets sitting on top of it and several coat hooks directly under the shelf. There was a wooden shoe rack on the wall adjacent to the coats, and a frame hanging directly over it containing the most important achievement of the Pines family aside from his father's promotion – the acceptance of his mother's first book to be published. She was ecstatic enough about the achievement that she went and bought both Mabel and Dipper both new cars – once the book sales garnished enough funds to support the splurge. In a way, it had been both a graduation present and an 18th birthday present.

"We can just go up to my room," Dipper told William distractedly, his eyes scanning the home for traces of Mabel. Safely, he assumed that she was already in her room. "Take your shoes off please, but they can be carried up to my room."

"Not gonna show me around?" the blond asked teasingly, "show me any embarrassing baby pictures?"

He shuddered at the mention of the photos and shook his head, "the tour can wait until before we go tomorrow. You'll probably get to see more than enough of the place while we wait for the moving truck to get here."

"That's how your stuff is going to the Falls?" William asked curiously as he peeled off his shiny black dress shoes. "We'll be going right after it?"

"Mabel will go first," Dipper told him as he did the same, then started off toward the spiral staircase that he and Mabel had loved to slide down when they first moved into the new home. "Show the movers the way, and we'll trail behind to make sure nothing's amiss. It'll be a straight drive to there." He looked back once to make sure the teen was still following him and was slightly relieved when he found that not only was he being followed, his every word was being latched onto with the rapt attention of the blonde.

"This is a really nice house," William repeated when they got to the second floor that he and his sister occupied together. "You sure you're not as rich as Pacifica?"

"Positive," Dipper replied as he walked over to his door and opened it, then walked inside. "We just have some really good connections and a rainy-day fund that my parents never told us about until the day before we went to Grunkle Stan's for the first time ever. It was also the first time we'd ever heard about his existence," he added.

The statement earned a grin from William as he strode into Dipper's room. He whistled lowly, "nice place you've got here."

His room was painted a simple light blue color that matched the color of the cap that he used to wear until it had become too tattered and had to be locked away in his special trunk, where he kept the original Journal 3 and the copies of the first two. His carpet was white, but he tossed a soft black rug over the majority of the carpet once he realized that his parents would be upset if he got it stained, only because it was so new. His bed was in the corner just to the right of the doorway, and his bookshelf rested a few feet away from the footboard, under a flat screen television that was mounted on the wall in the corner. There was a window on the wall right beside his bed, linking his room to Mabel's. The twins often kept it open, only closing it when they needed their privacy for things like getting changed. There was a simple black daybed near his walk-in closet that William was probably going to sleep on for the night.

Dipper nodded in acknowledgement to the statement, walking over to his walk-in and grabbing two sets of nightclothes. He studied one of the pairs intensely for a moment before holding it out to the other teen. It was a light blue set, with darker blue pine trees all over it, a mocking joke that Mabel had once made of his apparent nickname. "We look about the same size, so this should fit. You can change in here, or the bathroom's the door straight across the hall. Might wanna knock though – our parents disabled the locking feature after Mabel nearly overdosed on Smile Dip a year or two ago."

A dark blush crept up his neck as William set the pajamas on his sleeping place for the night and began stripping unabashedly in front of Dipper, a small smirk on his face.

"Okay then," he squeaked, turning around quickly.

William laughed lightly, "what? You're a guy – not like you've never experienced this before, right?"

"Not really," he mumbled in reply. "I wasn't really into sports, so I missed out on the whole athletic deal. Mabel doesn't count."

"Awkward…but, it's safe now. You can turn around."

Dipper did so, just as William finished fumbling with the last few buttons on the nightshirt. "I'll be right back," he mumbled, taking his own pajamas and dashing out of the room, praying that Mabel wasn't in the bathroom.

He'd just held his fist up to knock when the door opened up to reveal his sister in all of her post-shower drippy-haired glory, looking very surprised to see him. "Hi."

"He…" Dipper fumbled over his words, the flush that had just disappeared quickly rising up again. "He undressed. In front of me."

Mabel strode out of the room, grinning wickedly. "Wimp," she murmured not unsympathetically as she passed, ruffling his hair as she did so. "You make it sound like he tried to kiss you or something."

His eyes widened at the thought and his face grew darker in embarrassment. He spun around to catch her and ask the question burning on his lips, but she'd already retreated into her room.

He stepped into the bathroom and closed the door quietly, suddenly relieved to be left alone with his thoughts. "He's not…" he thought aloud as he peeled off his shirt and replaced it with a long nightshirt Mabel had once made for him, a light green with a fully decorated Christmas-themed pine tree on it. "He isn't gay, right? She would've…."

He sighed, "damn it. That's why she was grinning so much earlier, wasn't it?"

He was interrupted by a small knock on the door and the sound of William's voice penetrating the wood. "Are you okay in there? Mabel said something about you not feeling good….she asked me to check on you. Said it was a guy deal or something."

"Fine," he called back in as manly of a voice as he could muster as he stepped out of his slacks, leaving his boxers on and mostly covered by the Pine Tree shirt. "Thanks for the concern though."

Damn her, he thought viciously as he picked his clothes up and tossed them into the hamper, then opened the door to reveal a worried looking William. She set that one up on purpose…

The thought cut off as did most of his air supply when he finally got a good look at William. His scruffy hair that had looked oh-so-perfect at dinner had gotten ruffled, and if that hadn't been enough to makes his insides turn in an out already, it was the teen's dress. Or, his lack thereof.

William was still wearing Dipper's button up nightshirt, but it seemed that he had decided to forego the pants in favor of being in his boxers, much like he was.

The blond leaned against the doorway, his sudden smirk letting Dipper know that he'd been caught staring. "Like the view?" he questioned suggestively.

He stood there for a minute helplessly, his mind too jumbled to form any coherent sentences. "I…" he finally tried, his face growing darker. "I just really don't feel good." It ended in a high pitched squeak and William laughed.

"I'm sure," he told Dipper, grinning in an almost manic fashion. Nonetheless, he moved and Dipper used the opportunity to flee back to his room where he could hide under the covers in peace.

William walked into his room calmly just moments after he did, still chuckling quietly. "I didn't think that you were quite so skittish," he remarked as he settled himself down onto the daybed, snuggling under the few blankets that Mabel had probably left there for him. "It'll make for a fun summer."

"Wonderful," he muttered, his voice muffled from the blankets. He reached up and turned the lights off, closing his eyes in an attempt to shut out the rest of his mind.

I'm not gay, he told himself firmly. Mabel just seems to have it in her pointed little head that I am. It was a lie.

He rolled to his side and turned to face the wall that joined his and Mabel's room, sighing deeply.

A couple of years ago he'd told Mabel about his…conflict with his sudden attraction to guys. There was a reason he peeled away from society after that, aside from the occasional bully. He found that if he stayed away from everyone else, the odd feelings inside of him did too. Mabel accepted it more than anyone else that he'd told about it, and she sympathized with his plight.

Now, he mused as he slowly drifted off, it seems that my eccentric twinling is through her sympathy and is trying to set me up with William.

And strangely enough, he didn't completely mind.