As of today, Dipper Pines would be the first person to ever die of embarrassment. God, he just wanted to jump out of his bedroom window right now. Standing there in all of his gorgeous, golden glory, Bill fucking Cipher was wildly waving a photograph in his face. A photograph of himself in his lamb costume when he was a little kid. Dipper flushed and swore every curse word he knew as the demon laughed his trademark laugh.

"Awww, Pine Tree c'mon! Dance for me little lamb! Dance the lamby, lamby dance!" He taunted. Bill's face was stretched into a maniacal, shit eating grin as he howled with laughter.

Unable to even look at the sight in front of him, Dipper dove into the bed and buried his face in his pillow. "You were never supposed to see that! God, who even told you about that…" The last person – or demon in this case – he wanted to know about that was his asshole boyfriend. And now his worst nightmare had come true. He would never hear the end of this. He let out a frustrated sound into his pillow and kicked at his covers. He felt his bed dip, signaling that Bill had come to sit down beside his flustered form. Dipper shivered when a hand rested on his hair and began to trail downwards, fingers lightly scraping at his back before stopping dangerously close to his backside.

"Oh Pine Tree, you don't have to be so embarrassed you know~. I was just joking! I actually love this a lot. Honest!" Bill said, his fingers dipping under the waistband of Dipper's boxers. Like hell he was joking. The boy swore at him but the words were muffled and inaudible. The fingers paused for a long time, and Dipper reluctantly looked behind him to see the demon studying him intensely. He flushed again and flipped over onto his back, knocking the other's wander hand away.

"I know that face. What are you thinking?" asked Dipper, his eyes narrowing in suspicion.

Bill blinked in surprise as he was brought out of whatever he was thinking about, but that soon disappeared when a devilish smirk crossed his face instead. He leaned in and pecked his boyfriend's lips. "I just thought of something is all," He breathed, making Dipper shiver. Suddenly, Bill stood up and began to transform back into his triangle form. "Anyways~, I should probably go before Shooting Star barges in here."

Dipper got up after him, grabbing at the other's hand. "W-wait what? Something? What something?"

"You'll see."

Dipper sighed as he dropped his bag near the door and kicked off his shoes. Just another boring day at work again. Mabel had taken the day off today to spend some time with her new girlfriend, Pacifica, and Bill had left a couple days ago with no word of where he was going and when he was coming back. That just left him to try to entertain himself until one of them came back today. Reaching for the journal on his desk, Dipper paused when he saw the embarrassing photo beside it. His face scrunched up in annoyance as he covered it with the journal. Dipper laid himself back on his bed and stared at the ceiling. Where the hell was Bill? What was he planning? The longer this dragged out the more nervous he got. Dipper groaned and covered his face with his hands. Whatever it was he really just wanted to get it over with. Wiping all of his thoughts from his head, he closed his eyes and began to drift off.

To say his dreams were weird would have been an understatement. He was in a sunny, green field, and the sky was so colourful it was an eyesore. But what caught most of his attention were the countless lambs around him. They pranced about happily, bleating and eating at the lush green grass beneath them. 'Great' he thought, 'More lambs'. One of them approached him and began to lightly head butt his thigh, bleating gently. Dipper awkwardly patted its head, hoping that would satisfy it. It did. The lamb leaned into his touch affectionately, asking for more. He chuckled. Maybe this wasn't so bad after all. He continued to pet the cute little lamb, feeling less and less nervous about the situation. Well, until another lamb came to look for attention. And another. And another. And another. Okay, there were a little too many lambs now. Countless lambs began to crowd in on Dipper, turning the once green field into a sea of soft, white fleece. They climbed on top of each other in order to reach him, effectively burying him. The happy bleats were deafening and Dipper felt like he was drowning in the fuzziness. His whole body was now under the layer of fleece, and the bleats faded away as though he were submerged underwater. He couldn't see the lambs anymore, everything had turned into endless blankets of white, sliding against and caressing his skin pleasantly. Faintly in the background, he could hear his own four-year-old voice:

Well... who wants a lamby, lamby, lamby?

Oh god. Not that.

I do! I do!
So, go up and greet your mammy, mammy, mammy
Hi there! Hi there!

Dipper swam through the endless, writhing ocean of fleece, trying to find some sort of exit. He just had to get away from that. He thought he saw something yellow at the corner of his eye but it disappeared in the fleece when he turned to look.

So march, march, march around the daisies,

There was an opening in the fleece. Sunlight was shining through. Dipper frantically swam towards it. He was getting closer and closer.

Don't, don't, don't you forget about the ba-by!

"Oh, lamby~."

Dipper's nose twitched when something fuzzy tickled his nose.

"Wake up little lamb…"

He groaned in annoyance as he slowly began to wake up. Why was it so cold?

"Time to play, lamby~!" The voice said louder.

Dipper jolted awake and sat up, and he was met with mischievous golden eyes. "W-what? Bill? Why are you here?" The boy rubbed at his eyes tiredly. He paused when he saw something white and fuzzy hanging in front of his face. Dipper felt the white thing and trailed it up to his head, where he found that it was attached to a headband on his head. There were two of them, along with a silk bow. Lamb ears and a bow.

"Oh god…" Dippers eyes flicked down to his body and he gasped.

Dipper was wearing a light pink bra with white lace and bows, along with a matching skirt, if it could be called that, it barely covered anything! He shifted uncomfortably and discovered that he must have been wearing a thong too, a rather lacy one at that. He trailed his eyes down the pink garters to the lacy white thigh highs that were decorated by little pink bows. Dipper blushed. So… this was what Bill meant. He looked back up at said demon when he heard a chuckle. Dipper's eyes narrowed in annoyance.

"Seriously, Bill? A lamb?" Dipper tried to ignore the hand stroking his clothed calf. "What kind of perversion of my childhood are you trying to pull here?"

"What~? C'mon, little lamby, you know you wanna play…" Bill replied with an insufferable grin. He leaned in and whispered, lowering his voice, "Besides, you look delicious, Pine Tree. I don't think I can stop myself here."

Dipper bit his lip, knowing what would happen next if he agreed. They'd done stuff like this plenty of times before. "Fine."

"Well then little lamb… Now that you're awake, come play with me. I want my lamby." Bill's words ended in a playful growl and Dipper shivered as hands began to trail up his legs. Cool lips met his and the boy sighed into the increasingly passionate kiss. Dipper gasped as Bill began to massage his inner thighs, making him unconsciously spread his legs a little more. The demon smirked and took his opportunity to slide his tongue into the others mouth. As the two battled for dominance, Dipper's hands went down the demon's shoulders and chest. Bill ended up winning and Dipper could only moan and tug at the other's shirt as the demon's tongue explored his wet cavern. Bill got the message immediately, unbuttoning and throwing off his shirt to allow more contact.

Dipper laid himself back on the bed and pulled Bill down with him. The man began to trail kisses down his jaw down to his neck, where he kissed and sucked at the soft and pale skin. Dipper hummed and leaned his head back further, urging the other to continue. Every kiss and suck to his neck sent jolts of pleasure down his body and straight to his hardening length. Which, by the way, was beginning to feel rather tight for some reason. That was soon forgotten when he realized that Bill had slid the bra straps off his shoulders, pushing the bra cups down to reveal his rosy nipples. Dipper cried out when the demon took a hardening nub into his mouth and began to nibble and suck. Bill's hands slid down the boy's sides and roughly grabbed his ass. Dipper bucked and moaned as Bill switched nipples and swirled his tongue around the rosy nub.

"Little lamby likes it when I play with his tits, doesn't he?" he purred. Dipper shivered and moaned desperately when the warm, wet breaths hit his chest.

"Bill please!" The boy gasped. He arched his back into Bill, and the demon chuckled before sucking at the boy's nipple again, only this time rougher. One of his hands came up to pinch and tug at the other nipple. Dipper writhed in pleasure as both of his nipples were being played with. He reached down to stroke his length to find some relief but his hand was roughly grabbed. Soon both of his wrists were pinned above his head and Bill's face hovered over his. The demon's face had that devilish smirk again.

"Naughty lamby~! You're not allowed to touch yourself like that! Do you really need to come so badly?" Bill chuckled as the boy whined and writhed below him. "You need to learn to behave, little lamb~."

Dipper whined when the demon pulled back, but stopped when the demon began to undo and take off his pants. Bill saw that the boy was watching and he grinned, sitting back and spreading his legs. "Well? What are you waiting for? You've been misbehaving, now make it up to me."

Dipper bit his lip to contain a groan at the sight of the other's straining cock. He licked his lips and slowly crawled over to the demon, making sure to arch his back while he did to accentuate his ass. Bill seemed to like that, as he heard a groan from the demon. Dipper leaned down and bit the waistband of Bill's boxers, letting his teeth graze over the sensitive skin beneath. The man's cock sprang out and Dipper moaned when it hit his cheek, some of the precum smearing onto his face. He brought his mouth up to lick a long stripe up the hard cock. He licked and sucked at the tip hungrily, swirling his tongue around it and collecting the precum in his mouth. His eyes went to look at Bill, and he was pleasantly satisfied. Bill's face was bright red, his eyebrows drawn together, and he was breathing was erratic with the occasional gasp or groan. When their eyes met, Dipper only gave him a playful wink before completely surprising the demon. Dipper lightly bit into the tip, not enough to draw blood, but enough to hurt.

That seemed to make him snap, as the demon roared in pleasure and pain and grabbed at Dipper's hair roughly, pushing the boy's head all the way down his cock to the root. Dipper gagged as his nose was pushed into the demon's blond pubes, and quickly tried to relax his throat to recover himself. He had little time though, as his head was roughly pulled back until only the tip was in his mouth, only to be pushed down all the way.

"FUCK! Now you've really done it, eh? You want me to fuck your brains out, don't you, you little whore? Look at you, rock hard from just sucking cock and having your tits played with. Horny little slut, huh?" Bill panted as he continued fucking into the boy's mouth.

Dipper wanted to say yes to all of those things but they only came out as desperate muffled moans as his mouth was continually filled with cock. He sucked harder in hopes of conveying the message instead. Saliva began to trail out the sides of his mouth as he tried to suck, lick and breathe all at once. The hands in his hair were removed but Dipper continued to rapidly bob his head on the cock, deepthroating it over and over again. He felt his skirt get flipped up and his thong pushed to the side. The boy moaned into the cock in his mouth when a finger circled around his puckered hole, before sinking in. Bill's finger began to fuck into him and Dipper could only buck into it as he tried to continue sucking at the same time. His moans only got progressively louder when Bill added another finger. When the fingers grazed over his prostate, Dipper had to let the cock fall from his mouth as he screamed in pleasure. He got a hard smack on his ass cheek in return, making him groan in pain.

"Did I tell you to stop sucking, slut?" Bill growled, removing his fingers completely.

Dipper whined and bucked back as he put the demon's cock back in his mouth again. He sucked and ran his tongue over a particularly sensitive vein and Bill thrusted three fingers into his ass this time. Dipper wailed but made sure to keep the cock in his mouth. He was in ecstasy as the fingers thrust into his ass, continually grazing his prostate. However, they were soon removed again and Dipper whined in protest, jerking his hips back. Hands tangled into Dipper's hair and the cock thrust into his mouth all the way to the root. The cock twitched repeatedly and Bill moaned loudly as spurts of cum filled the boy's mouth. Dipper tried his best to swallow as much as he could but he was soon relieved when the demon removed the cock from his mouth and released the rest onto the boy's face. Dipper held his mouth open with his tongue sticking out, managing to catch some of the cum in his mouth. Most of it landed across his face however, and he had to close his eyes to avoid getting it in his eye. He could hear Bill chuckling above him.

"Slutty little lamb, this look suits ya. I should always have you covered in cum. Should fuck you like this every day. Would you like that little lamby? Hmm?"

Dipper turned around and raised his ass towards the demon. "P-please, Bill... Please fuck me! I need your cock in me!" He begged.

Bill chuckled and laid his hand on the boy's ass. "Well, I dunno, lamby. You did technically just have my cock in you." He teased, his thumb sneaking beneath the thong and stroking over the boy's slightly stretched opening.

Dipper moaned and bucked into his hand desperately. "Please, PLEASE! Please fuck me, Bill! I need your cock! I need it in my ass, please fuck my asshole!"

The demon tutted and pushed the lacy thong off to the side, inserting two of his fingers into the boy's hole. Dipper let out a frustrated groan. "Patience little lamby~! At least let me recover first!"

'Bullshit!' Dipper thought. The demon could recover in seconds, he didn't need that long! He just wanted to drag this out and it drove Dipper crazy. He let out a long, loud whine when Bill slipped in a third finger. The fingers began to rapidly thrust into his prostate perfectly and Dipper could only cry out in ecstasy as the urge to cum increased. However, just when he felt like he would, something stopped him. The boy screamed in pleasure and frustration as he was at his peak, but could not come.

"W-why? Why –ah!— can't I come?" he whined.

Bill laughed maniacally as his fingers quickened, ramming into the boy's prostate and making him scream. "You didn't notice yet, little lamb? Might want to take a look at your dick! You're not cumming until I say so!"

At this point Dipper was a moaning, panting mess, hair damp with sweat and face still covered in Bill's cum. With shaky hands, he did what the demon told him and reached down to yank the thong out of the way. He gasped when he saw that there was a pink ribbon tightly tied in a bow around his length, preventing him from cumming.

"Y-you asshole!" Dipper tried to shout angrily. Bill only laughed in reply.

Soon, the fingers were removed and Dipper groaned in protest. However, this was replaced with a long moan when he felt something hot and blunt push at his opening. "Ah! Yes! YES!" Dipper cried. Slowly, the tip slid past his tight ring and popped through.

Bill was breathing shallowly, wishing nothing more than to just fuck the boy to oblivion. But no, he had more self-control than that. He began to lightly thrust into the hot velvety channel, just letting his tip slide in and out of the boy's hole. Dipper let out a shout of frustration before his arms collapsed and his face hit the mattress. He bucked into the cock as hard as he could but his hips were held in place by the demon. God, he wanted to cry. His hole twitched and fluttered at the feeling of being penetrated and emptied again. He felt the tip slide in, and out, in and out. Dipper bit down on the sheets beneath him as he let out a muffled scream in frustration.

"P-please… fuck me hard…" He sobbed. Dipper canted his hips towards the demon as he begged.

"Alright. That's enough." Was all he heard until Dipper felt the demon grab the lamb ears on his head and yank his head up, the cock slamming in all the way. Dipper screamed in pain and pleasure as Bill began to fuck him. Tears ran down his cheeks as he did his best trying to will the stinging pain away. Soon, the pleasure finally began to overpower the pain and Dipper could enjoy the intense fucking. The boy wailed when the cock hit his prostate, sending shockwaves throughout his body. Finally. Finally. His eyes rolled back and his tongue hung out as the demon pummeled his hole at a demonic speed. He couldn't even think anymore. All he could focus on was that glorious cock sliding in and out of his willing hole. He could hear himself rambling on and on through a series of moans and gasps.

"Fuck me! Oh! Fuck me, fuck me, fuck me please! Harder! Ah! Oh, harder!" he chanted.

Bill was moaning and laughing behind him. "You like that don't you, you little whore? You've been waiting all night for me to fuck you like this, huh slut? Your tight, hot ass just keeps sucking me in! Can't get enough of this cock, can you? You like it when I fuck you senseless? Fuck, you got the sluttiest ass in Gravity Falls!"

Dipper panted and moaned in bliss as the rough and powerful thrusts into his ass continued without slowing down. The demon's hips slapped against his ass cheeks rhythmically. The dirty talk turned him on even more, as he pushed his ass back along with Bill's thrusts. "Yes! Yes! Your cock feels so good! I love it so much, I love it when you fuck me, I want it all the time!" Dipper cried loudly when Bill's hands trailed up from his hips to pinch and tug at his swollen nipples.

"Fucking slut. You don't love my cock. You'd let any cock fuck you as long as you've got one. Little lamb always wants a big cock to stuff his little hole full. Your mouth too, huh? Hey, here's an idea!- Fuck!" The demon cut himself off when Dipper tightened around him. "H-how's about I bring some friends over sometime, eh? I've got plenty of friends who'd love to fuck you silly."

Bill was getting close, so he pulled out, causing a loud protesting moan to come out of the boy. He flipped him onto his back, slammed in again, and continued fucking into him, watching his lamb's face carefully. "I'll tie you up and have you on the bed just like this. I'll let 'em in and leave 'em to do whatever they want to you. I can imagine it now. One cock after the other, no stopping for hours. They'll pump your ass full of cum just how you like it. You'll be sticky all over with cum. And by the end, you'll still be begging for more. You'll be so fucked up you'll spread your legs for anybody to get some cock in you."

The demon's thrusts were getting quicker and more erratic, but this didn't take away from any of the power. Dipper was completely out of it, all he could answer was "yes, more, harder, yes". All he could think about was the nine inches of cock sliding in and out of his quivering body. Sliding, tapping, stabbing against his prostate over and over, sending shocks of immense pleasure throughout his body. He could feel the cock twitching and pulsing inside of him, and he wanted nothing more than to have that cock paint his insides with hot, sticky cum.

The view Bill had was more beautiful than anything he'd ever seen. Dipper; with his face flushed red and sweaty, all covered in cum. His eyes were unfocused, and tears were streaming down his cheeks. His mouth was hanging open, his tongue lolled out and drool leaked out the sides. His bra had been hastily pushed down to reveal his hard, pink nipples, still wet and shiny from when he sucked them swollen. His pulsing, hard cock was out of the thong and resting against his smooth stomach, swollen and red from the pink ribbon tied tightly around the base of his cock. Bill watched as his cock disappeared into the boy's pink hole. Leisurely thrusting now, he watched how the red rim would catch onto his cock when he pulled out and how it stretched open to let him in. Dipper's ass and thighs had lube and precum all over, making a wet smacking sound when his hips made contact with the boy's ass. Bill's eyes trailed up to the cloth covered legs resting on his shoulders. The smooth, creamy skin that wasn't covered by the thigh highs taunted him. Bill pressed a kiss to the boy's inner thigh, before driving his cock hard and deep once more.

Dipper screamed once more in satisfaction, relieved that Bill decided to join him again. He reached for his legs and spread himself out more for the demon. "C-c'mon Bill. Cum in me. Fill me up. Fill up your slut." He murmured, his eyes filled with lust. This seemed to spur Bill on even more and Dipper was overwhelmed with the force of his thrusts. The headboard was slamming into the wall, and if Dipper's body weren't on fire right now, he'd be worried about damaging the bed or the wall. But that wasn't important right now because he wanted Bill to cum inside him. He wanted to cum.

Dipper cried out in surprise when he felt a sudden relief of pressure from his cock. Bill had untied the ribbon, freeing him, and so he was unable to control himself. Dipper's vision went white and the most intense orgasm in his life tore through his whole body. Screaming, the boy arched his back and clutched at the sheets as his cock spurted large amounts of cum, landing all over his chest, bra, and even up to his face. The orgasm had him clench down almost painfully on the demon's cock. Bill let out a loud shout himself when he felt his own orgasm bubbling. Cum streamed into Dipper's ass, and the boy moaned and clenched as his ass again, milking Bill's cock dry. Panting, the demon collapsed on top of Dipper, who was too tired to mind the extra weight on his chest.

"Wow…" Dipper breathed.

"Heh, yeah… I've got that effect… on people…" said Bill, still catching his breath. After he felt he was stable again, he pulled out of Dipper, causing both of them to groan in unison. The sight before him almost made him want to thrust into the boy all over again. Legs still spread wide, his cum was steadily gushing out of the other's loosened hole and down between those delicious cheeks. Bill had recovered already, but seeing as Dipper looked like he was going to pass out soon, he didn't think it would be very fun to start another round. Unfortunately. Instead, he snapped his fingers, a wet cloth appearing in his hand. He wiped himself off, and proceeded to clean his Pine Tree up too. As much as he enjoyed seeing his boyfriend covered in cum, he knew Dipper would be cranky later if he didn't do this now.

"Urgh, Bill…" Dipper groaned.

"Yes, Pine Tree?" The demon hummed, wiping at the boy's face.

"Why... What made you think this was a good idea?"

Bill laughed, "Well I just thought that since you're so hung up about this horribly embarrassing lamby lamby thing, I thought I'd turn that unhappy memory into a happy one. I think it went pretty well." Bill winked at him.

"Ugh, shut up…"

Bill carelessly tossed the dirty cloth behind him and climbed over to cuddle with his Pine Tree. He pulled the covers over them both, and nuzzled his face into the other's neck. He smirked when he saw all of the marks he left on Dipper's body. Just when he thought Dipper had fallen asleep, the boy looked back at him with wide eyes.

"Did you really mean it? A-about… your friends?"

Bill couldn't help but let a diabolical smile cross his face. "Of course!"

END.

WHEW, I'm glad that's over! If you guys liked this story, I'll be writing more prompt-inspired oneshots. Here are the ones I've planned for so far:

BDSM

Sirens and Pirates AU

Alpha/Omega Dynamics

Schoolgirl!Dipper

Nurse!Dipper

Haha, if you didn't already find out, I sort of have a soft spot for dressing up Dipper... I'm sure Bill would enjoy that too though. Anyways, let me know which of those you'd like to read the most, or, if you have your own suggestions, put it into the reviews and I'll be happy to try some of them out! Also make sure to give a review of this story too! Please be gentle with me though, this is the first smut fic I've ever written haha...