FrostIron, the AU, angsty drabble way. A friend wanted something both sad and happy, and this is what I cranked out. Vulnerability is afoot and ownership belongs solely to the brilliant minds of Marvel.

Mature, poignant and filled with a sacrifice that was very much intentional.

Despite what they said, hissed tenors of wrath and arguments bordering on violence, they would always return to each other's sides, aligned in a warped sense of tandem that defied any sense of self-preservation, the caul of hearts tearing with razor-words.

They had a way of revealing the worst areas of one another, skin peeling back to reveal muscle, twisted toxins from a past shrouded in vanity's epitome, the paramour of a worship of all that was and ever would be pettiness. Bone became scorn, hatred skewering the words that slipped through half-parted lips, mouths that inhaled for the sake of their life in the throes of profound passions. Eyes narrowed, emerald clashing with dark honey, wars raged to end, the fighting ceasing only to be reborn again and again, an unholy union of gazes rimming the air with slaughter-song, tainted amalgam giving birth to apologies, words whispered on ears that were only half-listening, half-hearing.

And then, despite their inevitability, circumstances altered, misshaping into a slight of hand that was always beneath the table, hidden with the behemoths of a roiling sea and poison waters: blood toxins spiking to a level that science refused to counterbalance for pure cells.

Books were scoured, eyes became shadows, hollowed with black thoughts, curtains and airs tumbling to the ground with the shattered tumbler glasses Tony was no longer able to hold. Skin the shade of sunlight, golden harmony meeting black hair became sickly yellow, ebony veins rippling beneath the flesh that silver lips on a silver tongue had once kissed, bitten, and tasted for his own delight. He tasted only ashes now.

Cures were sought, the nectar from the flowers around the Nine Realms said to cure any internal ailment, prayers were murmured by all, even by those who had no use for the gods, and doctors festooned wires and cords into a failing body, a body that remained in a state outside of comatose devices out of sheer willpower.

Mortality was their sheath and blade, consuming them with the forging fire and might it took to wield such a weapon, such a seemingly cursed desire.

But they had never been creatures of defeat.

Spells were cast, dark enchantments that left him tasting blood, his insides simmering with undulating flames. Beings were summoned that made him question the past reality of being considered a monstrosity, and answers were revealed, a truth that debilitated iron-clad conviction, ambition and future stripped from him with a nod of his head.

The thunder of a gavel rang in his ears, the pendulum severed his thread, and armor corroded, leaving behind an element of humanity he never thought he would join. Oblivion met him, subconsciousness a welcome stalemate.

He awoke, tangled in freshly washed sheets, machines revealing a medical miracle. Tony asked him what he had done, what Loki had signed away for the gain in his time to live. To which the once god replied not in words, but in a gesture: hands revealing tattooed runes across his chest, the backs of his legs, his eyes retaining simple existence only, green dulling to hazel.

"What did you do?" It was an inquiry borne on the remains of disbelief that he would do something so selfless for him, something that involved saving another human. Not only that, but joining them.

The words were not lead or silver, but gold, binding him to fate. "Nothing you would not have done for me."

It was an admission of their mistakes as well as an observation of naked light, chasing away second-guesses, relaying veracity.

Immortality was stripped from him, any thought of eternal regality splintering into what he knew to be a present decision, one without regret, without shame or anger at his compulsive desire. Immortality, he understood at last, his mind delirious and mired and filled with Tony Stark's scent, was what had been hindering him, his inability to choose a side, to seek an amity of species.

Not from Asgard, from Jotunheim, but a human. A human who bound himself to another human, giving away the most valuable price to the species he now belonged to: time's quantity.

Lips sucked the curves of his throat, hands gripping, caressing and urging his hips forward, every pore cherished, every breath tasted, life ringing in the room with the coming dawn, the coming moon. Afterglow settled amongst the components of a Valhalla he knew only when bound by these mortal restraints.

For, the immortal ones were truly the chains.

After, a question coiled through epiphany, a necessary query by Tony's kiss-bruised mouth. "Why would you do that for me? Why would you give up your life for me? I was dying, yeah, but why?"

They knew silence, for it spoke volumes, obliterating the physical cordon they manifested in their lives, knowing nothing but the stich-stich of bonds sewn by sacrifice and personal undoing.

It was in the flicker of his eyes, eyes that had once been a verdant green, the phantom smirk on his lips that revealed that Loki loved him. It was in the way Tony refused to move for a full hour, his movements frozen and left with only locked gazes, gazes that once sought to destroy the other, eyes probing, the scrutiny tender.

Gratitude came with trembling mouths, mouths that would talk, speak and communicate words from then on out, for it was an affidavit of promised sensation, an oath to protect and construct, instead of crushing the germination granted by an impulse year previous.

They had lost everything before; they had everything to gain now.

"...roam with me, come down to where all of the others fell. Get lost in the dark to find yourself..."