Chapter Text
Dipper was walking through the forest. This was a daily tradition for him, as well as it was usually the only alone time he ever got, and even then, his ‘Dipper Time’ was sometimes interrupted by Bill. Though, if Dipper was completely honest with himself, he never really minded whenever Bill tagged along (Even Mable got along with Bill, though Grunkle Stan was still way to apprehensive of Bill to even consider spending time with him alone and Dipper could kind of see why. Bill was a lunatic.). As long as he didn’t bring Dipper a bag of deer teeth, or a screaming head. Again. Stupid demon. Dippers’ favorite thing was when Bill decided to come along, and they just walked (or, in Bill’s case, floated.) side by side, and were silent or talked of nothing in particular. Though Bill was usually his classic sarcastic and morbid self, Dipper found that he really didn’t mind much. He had seen way too much to be bothered by Bill’s comments about how to disembowel a small deer or buck in under 20 minutes. Even hearing about Bill’s plans to take over the world didn’t bother Dipper anymore. He even helped with some of the strategy parts. Honestly, if Bill wanted to, Dipper would probably let him do his world takeover thing, and help (more), as long as his family didn’t suffer.
“FUNNY you should mention that Pine Tree!”
Dipper jumped when the echoing voice of Bill Cipher boomed throughout the forest. Of course he was listening. Bill was always listening and Dipper almost hated it.
“What do you want this time, Bill?”
Dipper sighed fondly, rubbing his eyes. Bill materialized his glowing isosceles form in front of Dipper, twirling his cane on his arm.
“WELL to start, I want YOU, DIPPER PINES, to TAKE OVER THE WORLD WITH ME and become my IMMORTAL CONSORT. Any objections? Because you will essentially become a demon yourself.” Bill loudly exclaimed.
Dipper sighed. He was expecting this would happen at some point, just not this soon, He wanted to get Mabel and his Grunkles, especially Ford, used to the idea of him dating a dream demon form hell BEFORE springing the ‘Hey I’m gonna take over the world with my demonic boyfriend!’ on them, because despite them not quite understanding his decisions, they were his family, and he didn’t want them dead. But what’s the catch?
“The CATCH, my dear Pine Tree, is that YOU have to BIND YOUR LIFE FORCE TO MINE so that you will NEVER die.” Bill said.
Wow. That really wasn’t all that bad. Dipper thought it was going to be something like ‘you need to murder 3 virgins’ or ‘kill some random creature in Gravity Falls’. Though Dipper did have one more question.
“And what do I get out of it Bill? It’s only a deal if both parties are interested.” Dipper mentioned casually, fully intending to take the deal either way, but he wanted to see what Bill had to offer.
“I’M GLAD YOU ASKED, PINE TREE! Once you have BOUND YOUR LIFE TO MINE FOR ALL ETERNITY, you will be able to ACCESS MY ENERGY and ACTUALLY BE ABLE TO USE MAGIC. Eventually. I’ll have to teach you but YOU’RE SMART so you should CATCH ON pretty quickly,” Bill said, watching Dippers jaw drop in amusement. His human really was fun. “So! What do you say, Pine Tree?” Bill said, holding out his hand which was engulfed in blue flames. “Do we have a DEAL?”
Dipper held up a hand in the universal cue to ‘hold your horses, I have one more goddamned question’. “Just one more thing. What will I have to do to become your ‘immortal consort’ Bill? What will happen?” Dipper asked.
“WELL, it’s ACTUALLY a lot SIMPLER than people think, Pine Tree. All YOU have to do is donate about 10 mL of your BLOOD, then let me worry about the rest. Souls are finicky, kid. They’re not something that you can work with without practice. THAT will come later.” Bill explained. Dipper nodded. It made sense. Dipper held out his hand.
“I guess you have a deal, Bill Cipher.”
OoO~~2 Weeks Later~~OoO
Dipper and Bill were slowly walking (or floating) hand in hand back to the Mystery Shack, not so eagerly awaiting the large talk that they’d probable get from Mable and Grunkle Stan for being out until 10:30 (and for Dipper looking like he just burned the whole forest to shit while standing in the middle of it all, which he did, but that was beside the point.).Dipper was finally starting to have some functional ability with this magic shit (After having bound his soul to Bill’s life force, which was a lot less painful then Dipper would have thought, and the process was really cool, in Dipper’s opinion). Where at first, he could barely conjure a small flame in his hand, now he could burn whole circles of the forest with barely a thought. Now Bill was talking about starting him on illusory magics, and after that, transformative magics. It all sounded quite fun to Dipper (who had absolutely no qualms about almost being charred to a crisp in the forest, since Bill had mentioned that before starting with the illusory magic, Dipper would need to teach his flames to not burn him, but that should be easy, since he already had such good control over them. He just needed to beat a little submission into them.)
As it turned out, they didn’t actually have to worry about Mable and Grunkle Stan. Mable had left a note saying that she was staying at Grenda’s house with Candy and Pacifica (though it was a wonder Mable got her to show up), and Grunkle Stan was going to be out late drinking (gambling) and wouldn’t be back until ass-o’clock in the morning.
Grateful for some down-time, Dipper collapsed onto Grunkle Stan’s recliner, while Bill shrunk himself down and made a nest in Dipper’s hair. Dipper still had yet to figure out why Bill did this, but it was cute, as well as comfortable, so Dipper wasn’t going to complain.
Dipper ended up watching old reruns of Duck-tective until the program changed, then he started the slightly precarious trek up to the attic bedroom that he and Mable still shared, for lack of a better sleeping place. Bill was so preoccupied with braiding three lone strands of Dipper’s hair together, that he didn’t notice Dipper had moved until he was being poked.
“Bill, unless you want to be drenched in hot water, I strongly suggest that you move.” Dipper said.
Bill grumbled, stood up on all fours and turned in a circle on Dipper’s head, before settling back down and continuing to play with his hair. Dipper just shrugged and rubbed Bill’s back with a finger (Bill’s edges might be fun to play with when he’s normal sized, but mini-Bill was like a paper cut waiting to happen). Bill just made a rumbling noise. Almost like a purring cat. Dipper found it really cute whenever Bill did it, which was never very often.
Bill went back to grumbling as soon as Dipper stepped under the spray of water. Dipper had always wondered why Bill disliked water, but the one time that he had asked Bill about it, he got a vague, half answer, so Dipper didn’t push it. One thing Dipper knew for a fact was that Bill liked was shower sex. Apparently Bill thought that Dipper was sexy when he was wet. Once Dipper had figured this out, he exploited it for all it was worth. And since there was no one home tonight, it was a perfect opportunity.
Dipper grabbed the soap and began lathering it over his body, sensually moving his hands over his body. Dipper focused most on accenting his hips, crotch, and ass. Dipper could feel Bill moving forward on his head to sneak a peek. Bill floated down in front of Dipper, returning himself to his regular size.
“What are you playing at, kid?” Bill asked.
“Nothing, Bill. Just thought that you might enjoy a little show, that’s all.” Dipper said, moving under the spray of warm water to wash the soap from his body. Bill’s body starts to turn a little pink at the mention of ‘a little show’. Dipper turns around to face Bill, funning his hands up and down one of Bill’s sides. Bill shudders. More like he vibrates, but fuck it, Dipper thinks, the word fits.
“You up for a little fun, Bill Cipher?” Dipper asks.
“Am I? Kid, you sure ask the DUMBEST questions. I’m always up for WHATEVER you have in MIND.” Bill says, snapping his clawed fingers, drying Dipper, teleporting them into Dipper’s room, and onto his bed.
With that, Dipper grabbed Bill, and put the small triangle in his lap, caressing his sides, while Bill, ever so kindly, ground down on Dipper’s dick. Dipper hummed. He was interested to see if sex with Bill was different now that they had been bound. Though, given the situation, Dipper guessed that he would find out pretty soon.
Dipper was pulled from his brief period of thought by Bill impatiently grabbing his hand and moving it between his legs to the opening that seemed to only be present when Bill was aroused. Since the surprisingly fleshy opening was present in the small triangle, Dipper thought that he was doing a reasonable job of pleasing the demon.
Bill let out a breathy sigh when Dipper pushed his fingers into Bill’s small opening. Dipper still, after so many times, could not believe how warm Bill was on the inside, compared to the cold exterior that Bill preferred. The difference in personality that Bill displayed when talking with others as opposed to Dipper was startling. If Dipper didn’t know that the demon liked to wear a mask formed of little emotion and quite a bit of hatred, then he to, would be filled with confusion when the demon was even remotely kind or generous. However, Bill had demonstrated a lot of both over the years that Dipper had known him; showing Dipper more of the secrets of the forest surrounding Gravity Falls, most of which were not included in the Journals, as well as showing him many comfortable resting places to escape from the hectic life that is working in the Mystery Shack. Bill gave him non-lethal flowers that could not be found in any other place but the forests surrounding the sleepy town; on one occasion, going so far as to give Dipper a flower that would connect their fates. For a being of pure energy with no weakness, Bill sure was insecure.
“I heard that Pine Tree.” Bill grumbled. “Now, let’s see how FAST I can hop on that PRETTY LITTLE DICK of yours, shall we?”
Dipper nodded his ascent. Sex with Bill was always interesting. Sometimes it involved bondage with fire, other times it was perfectly vanilla, aside from the fact that they were floating above Dipper’s bed (Mindscape sex was almost scary with the amount of tentacle that were usually present.). Though today, it seemed that Bill had settled on something relatively vanilla for their standards: teleportation. Teleportation sex consisted of Bill teleporting himself on and off of Dipper’s cock at slightly worrying speeds, then riding him for a good while, repeating this until they both came. It was really good for teasing and orgasm denial. Dipper wondered which one Bill would choose tonight.
“Ahh!” Dipper moaned as Bill phased himself into existence on Dipper’s dick, then quickly departed again, repeating every second. Looks like Bill decided that teasing would be fun tonight, though Bill seemed to give up on the teasing after only a short while, deciding instead to ride Dipper to completion.
Dipper arched his back when he felt Bill clenching whatever sort of cosmic vagina he had around Dipper’s cock. Apparently it did something for Bill too, because the action was repeated, Bill still moving up and down on Dipper’s member, clenching slowly increasing in speed. Dipper started to feel a familiar heat curling in his stomach.
“B-Bill-AH! Gon-gonna cum!” Dipper managed to say, despite the pleasure crowding his mind.
Dipper managed to last a good 3 seconds with Bill clenched around his dick before he was cumming. Bill clenched around Dipper’s cock once more before his… whatever fluttered.
“Mmmmm. That was a lot less KINKY than I had planned.” Bill said; casually sitting on Dipper’s crotch, with cum slowly dripping out of his… space pussy? (What do you even call something that a small demonic triangle can magically materialize on his person? A magic strap on? A plain old vagina? Dipper had yet to gather the courage to ask Bill about it, so for now, it’s a demonic vagina.) Though Dipper really didn’t know what he had been expecting from Bill.
Dipper sighed. “Damn it Bill!”