Chapter Text
Sif runs her tongue between her teeth, feeling their dips and curves, digging into the hard, sharpened bones.
There is an itch beneath her skin she cannot define, a prickle upon her neck she cannot describe. The warrior cannot remember it beginning, only that it crawls along her arms and flashes behind her eyes, hot in the back of her throat. It feels as if it has always been within her, buried quiet in her bones until now, clawing through her muscles and slick in the sinew of her limbs.
Sif wants; there is a hunger within her ribs, slick between her legs, burning stars beneath her fingers, but for what she does not know.
The warrior twists and turns in her battle stances, the leather grip of her glaive warm in her palm, the weapon slick with her sweat and worn from centuries of use. She feels the prickle beneath her skin fading as she moves, ebbing away like tides upon a shore, weaker and weaker as they rise against her. It is mere lust for battle she thinks, for the heaviness of armor and cloth over her shoulders and the burn of her muscles as she rips her enemies to the ground.
Sif does not wish to see the citizens of Miðgarðr in danger, but the training rooms of Avengers Tower can only do so much. She is Æsir, a shieldmaiden; conflict is her blood, the thrill of the battlefield maps her ribs.
She is the Goddess of War, and War is a fickle force, untamed and destructive, Chaos in his most ordered form.
“Sif?”
(Speak of the wolf, and he will stand at the door.)
The warrior whips around, hair long slipped of its tail and falling around her face, slick with sweat against her red-run skin.
The God of Mischief stands in the doorway, long and lithe beneath leather and cloth, adorned in gold. His hair is long, layered and curved wild around his face and over his shoulders, decorated with tails and braids by his own hands. The shadow of his cheekbones catches the warrior's eye, and her gaze follows the line of his jaw, down the curve of his throat until the high collar of his longcoat hides it from her view. The God's form is thin beneath his many layers, and the desire to rip them from him with her teeth overwhelms Sif, her eyes traveling down his legs and over his chest, finally meeting his gaze.
(Her curious eyes are not lost on Loki, but he says nothing; the rush of hormones after physical exertion is not unknown to him, and if she seeks him out with more teeth in her kisses than usual later, he will find nothing strange about them.)
“Stark has prepared dinner,” the God tells her, “Will you join them?”
Sif does not miss the way Loki says them and not us, but she leaves it be. Loki is still not entirely comfortable with the Avengers, and they not entirely with him, but they are all trying, and if he keeps his distance then so be it.
“I suppose I have been here long enough,” the warrior replies, gathering a towel from one of the nearby benches to wipe the sweat from her glaive. “Tell them I will join them shortly, then.”
Loki nods, turning his back on her and departing as silently as he had come.
Her gaze doesn't leave his body until she can no longer see him, the itch prickling beneath her skin once more, liquid upon her tongue and slick down her throat; an idea in her mind, forming.
(Watching him leave is second only to seeing him come her way, and she licks her lips as she unwraps the tape from her hands, desire dripping from her hound-teeth.)
When she finds Loki again, the God is in one of Stark's many laboratories. The protective glass walls are thick and reinforced, but Sif's hearing is sharper than any human's, and she can hear their conversation with ease.
Stark has Loki seated in a chair, the cloth and leathers of his ensemble draped over a nearby table. Electrodes and their wires are stuck to his bare chest, two strange antennae are secured to both of his ears, and Sif watches as the Tony pricks him with a needle. His blood is ruby-red and dark as it fills the chamber, and Sif licks her teeth, silent.
“You know, I was honestly expecting some Vulcan green out of you,” Stark comments, and the reference is lost on Sif, but his meaning is clear. “Can I call you Mr. Spock?”
“You may not,” the God growls, and the gravel in his voice prickles beneath Sif's fingertips, slides down her back like water. She secretly hopes the inventor prods him again, draws the low dark out of his throat even more.
“Your blood is red, you look like a human who got fed Miracle-Gro as a child, and you have the same color eyes as Captain America,” Tony rattles off, carefully arranging the samples for JARVIS to analyze. The whir and clicks of the equipment are quiet in Sif's ears, and the screens and holographic interfaces begin lighting up with data as the analysis begins.
“You're not nearly alien enough yet, you gotta cut me a break somewhere.”
Sif's ear perk up as the machines beep lowly, results flashing onto the screens as they finish, holographic models of DNA and various compounds and molecules rotating in view.
“Did I say 'yet'? I take that back, you're definitely an alien now,” Stark says, pulling various projections of enzymes and compounds down to eye-level.
“What is this?” he asks, turning to Loki with a complicated-looking structure in his hand. Sif recognizes it from the brief lessons in science and biology from when she was centuries younger, its form fresh in her mind from seeing so many of Loki's books over the years.
“That is Jötunn DNA, Stark,” Loki answers, raising a groomed brow in exasperation.
“It looks like a great icosahedron that got thrown into a blender and then run over by a truck.”
“All beings of Yggdrasill's hold are alike in their physical forms. Their DNA however, differs greatly,” Loki explains. “For example, you humans do not need to withstand high amounts of cosmic radiation, nor do you have the same capacity for magic or require the means to sustain it.”
“Magic is just science I haven't explained yet,” Tony muses, tossing the DNA structure over his shoulder and toying with other various substances floating around his head. Sif watches the billionaire like a child at play as he pulls apart the compounds, listening as JARVIS explains the theoretical function of each.
A few moments pass in silence until Tony whirls around, sitting on the stool in front of Loki, holding tight to what the God recognizes (too late) as a hologram of a sexual hormone.
(Unseen, Sif scratches at her neck, the faint watercolor of a bite mark staining her skin, and her smile is teeth.)
“So how do you all have sex?”
Loki's brow furrows in annoyance, a slight hiss escaping his teeth, pupils shrinking. The machine monitoring his brainwave activity begins to beep, the antennae on the God's ears blinking. Tony hops off the stool, tossing the hologram to the irritated Jötunn before patting a hand to his head.
“Easy there kitty, no need to be territorial,” the billionaire chides, typing rapidly into one of the computer terminals, stopping the noise. “It's a legitimate question; SHIELD requires that if you're gonna be loitering around on earth, I need to have a complete medical and anatomical profile on you, no holds barred. I also need to know in case your brother and Foster decide to want any little godlings running around and they need help.”
Sif thinks, and the sound of little feet is music to her ears, though she cannot discern why. It catches her off-guard, and her eyes follow the curve of Loki's throat.
“And don't worry about scaring me,” Stark says. “I've done some fucking weird-as-hell shit and there is nothing you can say that will faze me. Anything weird? Extra parts, tentacles, color-changes, freaky Avatar tails I can't see?”
“I can assure you there is nothing deviant about the mating of Jötunn and Æsir,” the God remarks, his voice dark, a bite in his throat.
“Mating? You make it sounds like we're talking about animals in a zoo,” Tony whines. “Next thing you'll tell me is that your societies have dominance hierarchies and females go into estrus.”
“Part of that statement is true, Stark.” The billionaire freezes, turning to look at the God again, slightly disturbed by the thin line of his lips in a sneer-like smile.
“So you either have an alpha-beta-omega system hardwired into your brain or your girlfriend is going to potentially go into heat at some point in time, in my tower no less,” Tony muses, brow tilted in hesitant belief. “But you're the God of Lies, so how do I know which one of those is true?”
“You don't.”
“And I'm going to assume that's the fun part,” Stark drawls, somewhat mortified by the God's conniving behavior.
“A woman of the Æsir is only fertile once every decade,” Loki begins, and Tony is instantaneously curious, grabbing his tablet from off one of the counters and typing furiously. “But for mortals, all of Yggdrasill's children are exceedingly long-lived, and do not need to reproduce so quickly.”
“Human women are fertile once a month,” Tony comments, “and we now have seven billion people running around on earth. You'd think we could learn from you guys.”
“An entire life for one of your kind is the blink of an eye to us,” Loki continues, “so it is no surprise that offspring are born to you so quickly.”
“But we don't exactly go through pon farr every seven years,” the billionaire quips.
“Ásgarðr is a realm of war,” the God explains. “Its population has been decimated many times in its thirst for power and glory. The mating drive ensures the continuation of the Æsir beyond the losses of the battlefield.”
“So you guys need some way to repopulate after you bite off more than you can chew,” Tony muses, fingers lightning-quick over the tablet screen. “Anything else I should know? Is Sif going to lock you in her rooms for a week and then rip off your head after she's done with you? Some creatures on earth do that,” and Loki's brow furrows in mild disgust.
“We are not so animalistic, Stark.”
“I could hide a camera in your room and find out.”
The God of Mischief flicks a wrist, the wires and antennae attached to his body falling to the floor, clattering loud in the silence of the lab as all of the computers and machines shut down. His clothes slide down to the floor, shadows moving across the tile to envelop him as he stands, adorned in golds and greens and blacks once more.
“You would do well to see that you don't,” the God of Mischief growls, pupils thin and cat-like, breath hissed between his teeth. He turns his back on the billionaire, leaving the lab as silent as he had come.
Loki pauses outside the door, a scent lingering faint in the air, hot on his tongue.
“Does the Man of Iron appreciate your dramatic touch?” and Loki turns, tasting want and fire in his throat. Sif steps from around the corner, a knowing, sly smile on her face and Loki knows she's been watching, listening the entire time, laughing.
“Of course he does,” the God answers, pulling the warrior against him, her scent inviting and luxurious around him, fingers digging need into the cloth of her tunic. “He would not entreat and bribe me for more otherwise.” Sif's fingers tangle in the tails and braids of his long hair, pulling his forehead down to meet her own.
“What could a mortal possibly bribe a God with?” the warrior questions against his mouth, trailing her tongue across his bottom lip, pressing her teeth into the angle of his jaw.
“He feeds my love of designer scarves, I feed his love of xenobiological study, and everything,” he says, fingers tugging her hair, pulling her mouth to his again, “is perfectly,” his hound-teeth scrape her cheek, kisses heated against her skin, “fine.”
Loki turns them both and lifts her, pressing Sif into the glass, rocking his hips into hers as he holds one of her hands against the window. Her mouth is hot against his own, something simmering beneath her skin, prickling against his own when they touch. There is a restlessness in her movements, in the curve of her fingers into his leathers and the husky sound of her breath in his ears. Something burns faint in her bones, a fire not yet stoked to fullness, and it makes him want her all the more.
The God presses himself into the warrior's body, her legs tight around his hips, digging into his back. He meets Stark's eyes through the thick glass as Sif digs her teeth into the crook of his neck, fingers yanking the high collar of his coat out of the way. The billionaire spreads his arms in disbelief and Loki knows the expression on his own face is sinfully debauched, and he moans loud enough for Stark to hear through the glass, rutting against Sif, eyes never leaving the scientist's.
Sif's hand trails down his front, pawing at his too-tight trousers and Loki's breath catches in his throat, giving Stark a feral, conniving grin as a flick of his wrist sends them to their rooms.
Tony crosses his arms, irritated, stomping away to find the most powerful glass cleaner in the tower.