Also written to Pompeii - Bastille. Crosspost from AO3.

Modi was about a three months and a half old when the healers finally, finally declared that Loki's body was fit for activities again. Of course, Thor had been ravishing Loki for quite a good while before that, but neither of them saw any reason to tell the healers that.

"But you must be gentle with him!" one of the healers admonished Thor, who had the good graces to cast his eyes down in a display of shame. Loki only huffed in annoyance, rolled his eyes and slapped away the healer's hands as she held them out to him to help him down from the bed. Byleistr, who was sitting in a chair beside Helblindi, grinned lasciviously at Thor and mouthed, "Goo won't slap to meat she mentally." In actuality, he had been mouthing "You don't have to treat me gently," but as Thor was not at all skilled at reading lips, he completely misunderstood and so Byleistr's efforts to woo the prince fell by the wayside. Loki, however, was not amused and shot a glare at his older brothers; Helblindi just arched a thin brow at him and shrugged noncommittally, and Byleistr laughed sharkishly (if there were such a thing, Thor thought Byleistr in that moment looked particularly like a shark from a children's movie Anthony had insisted he let Modi watch), and told Loki, "You know, lil' bro, you should learn to share. We could have a threesome!"

Loki looked positively revolted by the idea, but an inkling of something curled itself into the back of Thor's brain, to resurface at a later date.

Farbauti tutted from her seat. The Jotunheimr royal family had come to see Loki's physical examination (and, Thor suspected, Laufey had some sort of ice blade concealed under his robes if the healer tried to lay hands on Loki more than was necessary) before they went back home.

"Now, Byleistr dear," she said, laying a hand on her son's shoulder. "Be nice to your brother, you know how sensitive he can get about these sorts of things. And I'm certain the prince Thor does not desire to see your tattoos. From what I can recall, his skin was unblemished by ink of any sort."

Laufey took a second to glare at Thor above Modi's babbling form. The frost king was carrying the baby on his lap and bouncing him up and down. The baby had his fingers tightly curled in Laufey's robe, and Thor watched with amusement as Laufey bent his head down to coo at the little baby he swaddled in his arms. If Laufey felt any resentment about Modi's clearly Asgardian appearance, it wasn't apparent.

Ever since Modi had been born, Laufey had had to be coerced into letting go of the baby on occasion. He seemed absolutely entranced by Modi's little pink fingers, the rosy, chubby cheeks that crinkled in a smile whenever Modi caught a sight of a familiar face. Laufey could easily be found in the nursery, telling Modi stories of conquests and great battles he'd had, and more often than not, Jörmungandr would be curled around his shoulders as the baby snake listened in. Sleipnir, already a toddler, had been let out into the pastures where he galloped about with the other horses and four-legged creatures.

Frigga smiled from her corner of the ward as she knit yet another pair of baby mittens for Modi's little hands; Modi didn't particularly enjoy getting his nails clipped, and as a result, had taken to using Jörmungandr as a type of scratching post. Jörmungandr, who didn't have fangs yet, tried to bite Modi on more than one occasion after being scratched viciously across the back or the neck or face, with no success. He had stopped trying to slither into Modi's bassinet to look at him and instead preferred to look at him from a perch coiled around one of the cradle's posts. The little fat pink thing couldn't stand up yet, or do much other than lie there, and Jory was more than content to curl himself around a bedpost and stare at it with his beady little eyes.

The little serpent frankly could not understand what the fascination was his grandfather and everyone else had for this thing. It wasn't useful, it could barely move, it ate disgusting food, and it screamed at all hours of the day. And it was fat. Very fat. If Jörmungandr was any longer, he would have been able to wrap himself around Modi and squeeze, but as it was, Jory doubted he could get himself around (or under, for that matter) the baby, and so decided to leave that adventure for another day.

"Loki, sweetheart," Farbauti said, standing up and going over to Loki. She smiled and pinched both of Loki's cheeks in slender, blue fingers, and Loki returned her smile. "Believe me, nothing would please your father and I more than if we could stay here in Asgard and watch Modi grow up, darling," she continued. "But as it is, the Asgardian weather is far too hot, Helblindi's skin is flaking off!" Here she indicated Helblindi, who had taken to slathering himself in baths of aloe vera and various gels, to no success; he resembled Jörmungandr, his skin patchy blue and darker blue, and Thor had to conceal his laughter every time the frost prince passed by in a huff. He'd always thought Helblindi a bit of a prat.

"I know, Mother," Loki said, pouting slightly. "I wish you could stay also. But I'll be sure to bring Modi by Jotunheimr sometimes."

Farbauti grinned broadly. "Your father and I would like that very much, dear," she said, speaking for Laufey, who was giving Modi Eskimo kisses. The baby seemed fascinated by the red etchings on Laufey's cheeks, and patted little palms all over them, tracing the upraised flesh.

Laufey had never looked so happy, at least not in Thor's knowledge, but when he caught Thor looking at him and Modi, he peeled back his lips in a vicious snarl. Thor only rolled his eyes (he'd picked up that habit from Loki, of course) and, when Laufey's attention was diverted once more by Modi, who was now blowing spit bubbles, Thor quickly snapped a photograph with a small Midgardian device Tony had called an eye phone. Thor thought it was rather strange; the small silver rectangle had no eyes, at least none that he knew of, but it was rather useful and was suitable for capturing moments in time.

Tony had given up on trying to teach Thor how to use the phone after the god had smashed three in his attempt to free the people inside.

"Loki, beloved," Thor said that night, after Laufey and company had left, and the children were sleeping quietly in the nursery. Loki was perusing some Midgardian magazine, pursing his lips at the beautiful women the catalogue contained and hissing that if he had PhotoShop, he'd be much more captivating than any of these wenches. Thor had no idea what PhotoShop was, of course, but he only smiled and patted Loki's hand fondly, telling him that he was the most beautiful being Thor had had the good fortune to ever look upon.

Once Loki had put the catalogue on the nightstand, he turned to Thor. "What is it?" he asked, arching an eyebrow at him. "You wanted to say something to me?"

"Ah, yes, that's right," Thor said, with a broad smile as he remembered. "Bystar said earlier something about a threesome?"

Loki just stared at him.

"You know, your brother, Bighorn?"

Loki rolled his eyes and reached over to blow out the candle.

"Are you averse to the idea? It doesn't have to be with Blibinski."

Loki snorted as he cuddled up next to Thor, who drew him into his arms and ran broad fingers through Loki's silky hair.

"I will...consider the idea Byleistr so kindly brought up," Loki muttered after a while.

Thor could hardly contain his delight.

"You've got to be joking, right?" Tony said when Thor told him of his search for a third person to partake in explicit endeavours with him and Loki. "You're asking me?"

Thor nodded eagerly, smiling innocently at him, completely oblivious to the fact that Tony was currently holding Pepper's hand. He was also completely oblivious to the fact that Tony and Pepper were in the restaurant of a skyscraper, dining on the roof, and Tony was down on one knee holding open a tiny velvet box.

"Let me just tell you, man," Tony said, sighing, "you have literally the worst sense of timing. Or of situation perception."

Pepper smiled broadly at the two of them, shook her hand in Tony's slightly. "Of course I'll marry you, Mr. Stark," she said, with a laugh.

As Tony smiled in relief and slid the ring onto her finger, she craned her neck back to look at Thor, who was floating in the air right off the parapet. "Can you film the encounter?" she whispered, so Tony couldn't hear. "I want to watch it later."

As Thor flew away, he made a mental note to ask Loki how to work the video camera.

Bruce looked at him oddly when he asked him if he would like to be the lucky individual.

"No, Thor, I don't believe I would," he stated after a very long while before turning back to his microscope and fiddling with the dials. "I'm not sure Loki has quite forgiven me for slamming him around that one time. And calling him puny."

"He does have a bit of an ego problem," Thor agreed.

"A puny problem, one might say," Bruce said, chuckling to himself as Thor left the laboratory.

Steve eyed him suspiciously the instant Thor stepped into the tower gym.

Thor opened his mouth to ask, but the instant he did so, Steve's arms froze above his head, where he was bench pressing 250 pound weights. They remained in the upright and locked position, like an airplane tray table, and Steve stared Thor down until he closed his mouth, at which point he began lifting again.

Thor opened his mouth again, to the same result. It was really quite amusing, but after about half an hour of this stop and go, he decided that it would be rather imprudent to cause Steven to drop the weights on his head.

Humans were rather fragile creatures.

Clint and Natasha weren't much help either. They suggested everyone and everyone in the Midgardian universe, including but not limited to the Dalai Lama, the President of the United States, and Vladimir Putin.

And while Thor had heard much about this Vladimir Putin fellow, and seen many pictures involving the man shirtless and riding a bear across the wilderness, he was relatively sure that Loki would not be pleased with any of the 7 billion options available.

And of course, it was probably not wise to ask Natasha this while she had a whip in the air and Clint was tied to the bed.

Thor quickly departed.

Thor even went to Nick Fury's office one fine Saturday morning, rapped on the door, and was invited in.

When he told him of his troubles, Fury just stared at him out of his one good eye.

"Son," he said with a heavy sigh, and Thor wanted to politely tell him that he was not, in fact, his son, but Nick cut him off. "There is no way in hell I am having sex with that motherfucker. Or you, for that matter. Now please, get out of my sight before I castrate you."

Thor had no idea what castration was, but it didn't sound particularly pleasant, and he hurried out of the office.

"I have given this idea of yours some thought," Loki told him when he returned to Asgard a few days later. He was in the middle of feeding Modi a bottle of formula, and the baby was snuffling and mewling in his arms, causing Thor to smile down at the two of them and completely forget whatever his idea had been.

He looked up at Loki, confused. "What idea was that?" he asked, putting a finger in one of Modi's open palms and grinning broadly as the baby gripped tightly.

Loki rolled his eyes and sighed pointedly. "A threesome. You said you desired to have one."

Thor was fascinated by the way Modi's tiny fingers opened and closed around his own, so much so that he didn't process Loki's question until Loki gave an exasperated huff and snapped his fingers in front of his face, sending a stream of golden sparks flashing up into his eyes. Batting them away and blinking a few times, Thor finally looked at Loki again. "Ah, yes, that's right, I suppose I did say that. Have you come to a decision, fairest?"

"I have, as a matter of fact. I will simply make a duplicate," Loki said, matter of factly, as he shifted Modi to his shoulder and gently patted his back. The baby let out a tiny burp that had Thor making rather unmanly noises, and Loki rolled his eyes again.

"A duplicate of you," Loki clarified, as Thor bit his knuckle to stop from squealing in fascination and simpleminded delight as Modi rolled over and smacked his tiny lips. "The two of you will pleasure me."

Thor only nodded in acceptance and continued smiling and cooing at Modi, who was now gurgling up at his father and tangling his fingers in Thor's beard.

Loki allowed himself a small smile as he handed Modi over to Thor, and departed to his chambers to research the appropriate spells.

Thor examined the duplicate suspiciously. "Do I really look like that?" he asked, eyeing the broad planes of muscle Loki had created. "Don't you think that's overexaggerating my features a little bit?"

The clone's sky blue eyes peered back at him. They were an intense shade, but incredibly blank, and Thor felt a tiny bit unnerved looking at Loki's creation for too long.

"No, of course not, it's fine," Loki called to him from his position on the bed. He was already naked, and seemed to have no qualms about spreading his legs and shaking his hips provocatively at Thor and the clone. The clone watched in disinterest, and Loki waved a hand, beckoning the clone over. Thor hung back, watching as the clone clambered onto the bed, sturdy limbs encasing Loki, strong hands pulling whimpers from Loki's mouth as long fingers wandered over Loki's flesh, pinching, pulling, stroking.

Thor drew the line when the clone bit kisses up Loki's neck and pressed his lips to Loki's.

"No, no, no," Thor said, pulling the clone back. "Only I can do that."

And Loki wasn't sure, it was sort of dark in the room, but he could have been willing to bet at least fourteen cakes that Thor was actually pouting. Pouting.

Loki grinned helplessly as Thor pushed the clone aside and leaned over him to press a kiss to his mouth. Thor's tongue slid easily in between Loki's lips, pressing, tasting, rolling around his teeth and inciting his own tongue to action. While Thor had his hands buried in Loki's hair, Loki twitched his fingers, beckoned the clone to kneel between his legs. He smiled into the kiss as he felt the clone's hands - so much like Thor's, down to the lovely smooth skin at the base of the left thumb where Thor had been badly burnt a few centuries before - press down on his hips.

Loki gasped and arched up underneath Thor as the clone lowered a warm, wet mouth down onto his cock. Thor pulled back, curious, looked back to see the clone with its nose buried in the damp curls at the base of Loki's erection. And it was odd, it looked so much like him, but Thor didn't particularly like the clone's expression, it was far too dead. He leaned over, hesitantly placed a palm against the clone's forehead, and gently slid it down to close the clone's eyes. Loki eyed him curiously, not stopping the circular motion of his hips.

"What was that for?" he asked, in between soft gasps and whimpers and moans. "Don't like it?"

"It is unnerving," Thor admitted, watching himself suck Loki off. "It is better like this."

Loki rolled his eyes and reached up to tangle his fingers in Thor's hair and drag him down for another kiss.

Loki had insisted earlier, after his first orgasm and before his third, that he have both of them at once. He absolutely would not be satisfied without both Thor and the clone inside him, at the same time. He was definitely loose enough, he assured Thor, he hadn't had the two of them pressing fingers and tongues into him for no good reason.

Thor was hesitant, at first, not wanting to hurt Loki, but Loki had rolled over, glared viciously at him in a manner that Laufey would have been proud of, and told Thor in a no-nonsense tone that if he wasn't willing to indulge him Loki could easily set him and Byleistr up on a date, the other frost prince had been talking about it for the better three quarters of the past few centuries. There was nothing in the nine realms that Thor wanted less, so after a bit of coercion and an assortment of threats, he nudged the clone aside to kneel between Loki's legs.

Thor slicked himself up with oil, stroking, once, twice, thrice, before Loki cleared his throat in impatience and looked pointedly down at himself. Thor smiled fondly at Loki's familiar impatience before gently pressing into him.

Loki almost instantly had his hands on Thor's shoulders and was pulling himself up so that he was sitting, knees on either side of Thor's hips, and the clone was positioning himself behind Loki. Thor waited with bated breath as the clone wriggled its hips, broad hands settling underneath Thor's on Loki's waist, and began working itself in.

And if Thor had thought Loki was tight beforehand, he was even tighter now as the clone squeezed its way into him beside Thor's cock. Loki shuddered, burying his face in Thor's neck to muffle a whimper as the clone finally settled in place inside him. He felt incredibly full; he could barely breathe without feeling a swell of pleasure roll over him and crest in the pit of his stomach, which was already roiling with heat and need and desire.

And then Thor gave a hesitant twitch of his hips, and if that wasn't Valhalla, Loki wasn't sure what was.

Loki could barely see for the lust clouding his eyes, was barely aware of his fingernails leaving bleeding red crescents in the skin of Thor's back, could barely think or breathe what with the jagged spikes of pleasure piercing through him every time Thor or the clone moved. The two had taken to moving in counterpoint to each other, so that Loki was never left completely empty, so that there was constantly a hard length pressing up against his insides and his prostate, sending shudders and electric heat up his spine.

"Thor!" Loki cried out, sobbing as Thor leaned forward and bit a kiss into the sensitive skin of his neck, right above his pulse point.

"How does it feel?" Thor asked, and he wasn't proud to find that his voice was shaky, as close as he was. "Is it enjoyable?"

"Norns, yes," Loki sobbed, throwing his arms around Thor's shoulders and hugging him close, nuzzling up against Thor's beard. "Good, fantastic, please, I need -"

This last word was drawn out in a high-pitched keen as the clone gave a particularly rough thrust, and suddenly Loki was clutching tight like a vice around the two of them, his body tense and rigid in their embrace, before he gave a little half-gasp, half-squeak that Thor had never heard before and suddenly Loki was painting his stomach with white.

His insides clutched rhythmically, tightly around Thor and the clone, and Thor bit into the soft skin of Loki's neck, tasting blood as he spilled himself into Loki.

The clone did have its uses, Thor thought absentmindedly as he watched Loki send the clone to the other side of the nursery to tend to a cranky Jörmungandr, whom Modi had rudely awoken from his midmorning nap. Watching the baby snake coil itself around the clone's shoulders and bite ineffectually at its neck, Thor turned to Loki, who was playing patty cake with Modi.

"Loki, dearest," he began.

"What is it now?" Loki asked, switching to peek a boo and causing Modi to squeal in delight. "What other absurd ideas might you have?"

"Do you think it might be possible for you to send that clone to Jotunheimr? For Byleistr. He's sent me no less than forty-seven letters this week alone. All rather explicit. And while I respect your family, I have no desire to inspect this 'tramp stamp' he has gotten. He told me it featured Mjolnir. Perhaps the clone could do it?"

Loki rolled his eyes and said nothing, and Thor decided not to bring the matter up again.

A week later, Byleistr would wake up and would open his chamber doors to find the clone standing outside his bedroom. The clone returned his sharkish smiles with equally fangy grins of its own, and Byleistr would be smitten instantly.