SUMMARY: on-the-star-side said: Just saw your post looking for prompts. I imagine you want most being starker and thorki since they are the basis of the hate. And they should be mostly filled for those groups I get that , but can you also consider shota peter and top Stephen Strange.

AO3 TAGS: Alternate Universe, Alternate Universe - Canon Divergence, Adult Stephen Strange, Underage Peter Parker, Shota Peter Parker, Pseudo-Incest, Uncle/Nephew Incest, Underage Sex, Extremely Underage, Anal, Anal Sex, top Stephen Strange, Bottom Peter Parker, Prompt Fill, Spitefic

AN: My dude, I'm up for anything. lol So I can and will consider that, absolutely. :3 (Also sorry for the lateness, this prompt was stuck behind that last prompt that was weirdly difficult for me.)

FFN Only Notes: And this is my first Crossover since apparently whoever's running this site didn't put the Doctor Strange characters into the Marvel category... For some reason...

"Uncle Strange!"

Stephen looked up at the shout and smiled at the small boy tugging his foster father into the New York Sanctum.

"Good morning, Peter. Stark."

Stark gave him a mock salute and finally released Peter's hand, releasing him like a bullet straight into Stephen's legs - it was only through the grace of the Cloak of Levitation that Stephen remained upright. Still, he laughed, amused by the energetic greeting, and the Cloak went a step further, parting the child from his shins and lifting Peter into his arms.

"Can we play the sitting game today?" Peter asked excitedly, sending Stephen's pulse racing.

"The sitting game?" Stark echoed, poking around at things he shouldn't knowing damn well he shouldn't be.

"We float in the mirror realm and read about magic and have a good time, don't we, Peter?" Stephen replied, smiling down into the eager face of his favourite (and only) foster-nephew and pretending he wasn't getting completely and absolutely hard.

"Sounds fun and exciting," Stark said dryly, finally ambling over to them. "I'll be back in a few hours, Peter," he said, ruffling Peter's hair. "That's how long you have to wreak all the havoc your curious little heart desires."

"Bye daddy!" Peter yelled, waving excitedly, nearly hitting Stephen in the face.

"How kind of you," Stephen said even drier, and practically shoved Stark out the door. After it closed, there was a few blessed breaths of silence before the child on his hip started bouncing in place.

"Sitting game sitting game sitting game sitting game," Peter chanted under his breath.

Stephen turned a smile on him. "Of course, Peter."

He pulled a book to him, one that he'd read before to make the game a little easier, and crossed his legs, falling back and trusting his cloak to catch and lift him off the ground, as reality glitched around them. Peter clapped excitedly on his hip, his brown eyes gleaming with wonder, bouncing even as Stephen pulled the boy across his lap.

"Don't forget, you have to be still for this part," Stephen said kindly, and Peter fell still, though his little body trembled with trepidation - not that he was afraid. This was his favourite game to play when he came to visit Stephen, and Stephen would be lying if he didn't say it was his favourite too.

Peter clapped when the Cloak of Levitation lifted him upside down by his ankles, and he giggled and shrieked his way through Stephen licking him open, getting the boy nice and wet. The hard part, pun intended, was always when the Cloak turned Peter right side up again and held him with the head of Stephen's cock against his hole, keeping the little boy steady.

"Are you ready to play?" Stephen asked, craning his head around to look Peter in the face.

Peter met his eyes and grinned wide. "I'm going to win this time, Uncle Strange!" he declared.

Stephen grinned. "Best of luck to you then, my worthy opponent."

Peter giggled, but the sound choked off when the Cloak pulled the boy down onto his cock, his expression becoming a confused grimace. He was too young to understand the sensations of being spread open on a cock, didn't understand the pain of the stretch or the pleasure of being filled, but Stephen sighed in relief at having the tight walls fitting like a glove around his cock. It truly felt marvelous, being taken in like that. Vaginal sex was all well and good, but nothing squeezed quite like anal, and nothing felt quite so tight as his little foster nephew.

When Peter was nestled completely in Stephen's lap, stomach bulging slightly from being impaled on an adult cock, the Cloak floating free again, Stephen stroked his hands through the boy's hair and pressed a kiss to his temple. "Would you like to stay in the game, Peter? Or would you like to yield?"

Little fists were wrapped tight in Stephen's pants over his knees, and when he turned Peter's face towards him, Peter's eyes were squeezed tight and he was biting his lip. Stephen gently pressed his thumb on the boy's lip, easing it out from under his canine, and Peter finally opened his eyes, revealing brown eyes gone dark with fully dilated pupils.

"N-no, Uncle Strange," Peter stuttered out. And slowly, he managed to straighten, managed to unclench his fingers from the fabric over Stephen's knees, managed to release the tension in his little body bit by bit until he was sitting plianty on Stephen's cock.

"Such a good opponent you are," Stephen praised kindly with a pat to Peter's head. As he placed a hand over Peter's belly, his Cloak delivered his current reading into his free hand. As soon as he opened the book, and positioned it just high enough to read over Peter's head, he began to rub and read out loud.

"Astral projection is the method of…"

To Stephen's knowledge, everyone who'd ever visited the mirror realm had experience in manipulating their surroundings, but no one had ever tried manipulating themselves. Stephen, however, was not most people. As he rubbed a slow circle counterclockwise on Peter's belly, Stephen could feel his own cock shrinking, and Peter relaxing with the decreased intrusion. But a clockwise circle, a reverse, returned Stephen's cock to its natural size, and the growth inside the soft, warm, wet walls of the boy in his lap was like a silky massage, sending trails of pleasure down Stephen's spine.

"Each user's experience is unique, though similar…"

The 'game' was really more for Stephen than Peter, who was still too young to experience orgasms of his own. For Stephen, it was a test of self-control, it was meditation, it was studying, it was practice in focused multitasking. Because he couldn't stumble on any word, and he couldn't lose the counterclockwise-clockwise motion of his hand - either one would be a loss, and he'd have to actually start teaching Peter magic. That was the deal. As long as he didn't lose his place or his rhythm though, he won.

It was the easiest game Stephen had ever played.

"Though a common tool, it is often the hardest to achieve…"

For Peter, however, all he had to do to lose was tap out or speak. And if he lost, then they wouldn't play the sitting game the next time Peter came to visit.

Perhaps unsurprisingly, every game thus far had ended in a tie.

The delightful thing about touching Peter's stomach as a way to manipulate his own penis was that Stephen got to feel the return of his normal size behind the boy's belly. From the inside, he got to feel the way Peter slowly got tighter, like the filling of a blood pressure cuff, gripping him tight and massaging his length with quivering muscles. From the outside, he could feel the bulge pushing against his hand. Stephen was hard pressed to say which sensation was the one to cause the stronger tingles along his spine or the heat in his own belly.

"Many non-magick persons have claimed…"

It was so easy for their games to last hours. The pleasure was a low simmer, like a vibrating bullet on the lowest setting set against Stephen's taint. It took concentration for his pleasure to build into an actual orgasm, but oh was it worth it. Slowly, as the pages turned, Peter lost his capacity to remain still. Though the sensations were a little confusing to a small boy, children nonetheless often discovered masturbation and were shameless in exploring the strange, new, wonderful feelings of it. In that, Peter was no exception - when he could no longer remain still, he began to squirm, shifting in Stephen's lap, possibly seeking a more comfortable position, or possibly just exploring the feeling of his prostate being stimulated.

"It is vital to always be in a safe place when projecting for…"

Stephen didn't mind though, even if he kept having to raise his book to see over the rolling motion of Peter's head. Each of Peter's shifts incidently squeezed Stephen's cock, and even after spending countless time with almost-too-tight walls wrapped around him, that extra squeeze, that extra pressure, that extra stimulation, turned the near-gentle frissions down his back into near-violent sparks that sent his blood boiling. It was those little shifts that nearly undid him each and every time because it was those unexpected squeezes that made his breath hitch in his throat, made his blood boil and his orgasm near breaking point.

"In a similar vein, one must always know where their body is located…"

Despite being incapable of orgasms, Peter was still capable of getting hard, and every touch to his small but erect penis made the boy go rigid and clamp down hard around Stephen's cock. Now that Stephen was slowly nearing the point where he could easily come, he began to brush Peter's cock with every clockwise brush of his hand, so that each growing of his cock was met with a welcoming, beckoning hug of warm, wet muscles. It was like he was being pulled deeper inside, as if Peter's muscles were pulling Stephen's cock into where it belonged - so deep into Peter Stephen could feel the nudge of his glans against his palm.

"In conclusion…"

He was so close he could almost taste it - so close, in fact, that he was able to signify the near-ending of their game by finishing the chapter and closing the book. That tension deep in his belly, the tightening of his testicles, the near-burning at the base of his spine. As a doctor, he'd been so used to looking at the body for all its parts, so used to looking at it in terms of the medical that he often forgot about how it all went together, how it all felt. But when he actually came, when the pleasure all coalesced and spilled out, Stephen forgot all about the pattern of muscular convulsions, the flood of chemicals in his brain. In the end, it was all just heat and pleasure, his hand having fallen still and pressed so tight to Peter's belly that Stephen could feel each pulse as semen was pushed out his cock and into Peter, filling up his nephew.

It was only a few seconds for the pleasure to fade away, but Stephen's cock was still pulsing, and each palpitating press of his hand against his glans between pulsations sent a sensation down Stephen's back that was almost too much. He didn't stop until the gentle throbbing in his cock slowed and stopped, and after it was all over, there was nothing in the mirror realm but stillness and heavy but measured breathing.

"I won!" Peter declared in a scratchy voice, breaking the silence.

Stephen chuckled, and the Cloaks' corners rose and petted over Peter's bare skin, making the boy giggle and squirm on Stephen's too-sensitive cock, making him bite his lip. "Did I lose then?" he asked, amused and strained from the slight over-stimulation.

At his question, both Peter and the Cloak stilled. "...No?" Peter said after a moment of thought.

Stephen ran fingers through Peter's hair, unable to resist touching though the messy strands were in no worse condition post-game. "Then what is it called when neither of us wins and neither of us loses?"

"Hmmm…." Peter trailed. "A tie!" he exclaimed triumphantly.

"Exactly. Such a smart boy you are," Stephen praised. Peter flushed and squirmed like he didn't seem to during their game and it made Stephen smile.

There was a brief silence, one in which Stephen was content to relax and settle down, to simply pet Peter.

"Well… if I didn't win… and you didn't win…" Peter said slowly, apparently thinking out loud. "Then we should play again, Uncle Strange! Maybe one of us will win this time!" he said with the hopeful enthusiasm only the innocent could achieve. It made Stephen's chest warm. And his cock hard.

"Game on."

FIN

I feel like I keep finishing my SWNs on dialogue… Hm… Overall not exactly happy with this one but I also wrote it at like 6am and was dead tired and I went to sleep instead of posting and now that I'm awake I'm just gonna post it without reading over it so hopefully it was uh… readable.

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