Disclaimer: I own nothing, I make no money.

Author's Note: ThunderheadFred, come collect me. I am ruined.

Rust

"Shepard notices it like a sudden splinter, a prickling of awareness beneath her skin, adamantly wedging itself into her periphery." - Shepard and Mordin. Love quietly realized.

Through the filter of her visor's read-out, the clinic is dimly lit and red-hazed. Static to the eye, but Shepard has only one focus.

Mordin Solus says many things and nothing all at once. His hands are anything but stagnant, his eyes blinking rapidly as he paces through his single-minded monologue. He passes under a cone of light, his skin like rust, pock-marked, leather-lined.

She thinks of the red clay back home, its grated texture in her palm when she digs her fingers into the earth. And then she wonders how she still remembers these things – these things she had always thought would be lost once she died. But memory is heavy in her palms, in the still-healing seams of her skin – gleaming a faint red, like the sun glinting off that clay back home.

She still isn't sure if even that is fabricated as well – just like her.

"Does he ever shut up?" Zaeed mutters beside her.

Shepard offers a single raised brow his way in answer.

Mordin blinks at her, suddenly silenced, stilling mid-pace with one hand halted in the air. And then the edges of his mouth tilt up in something of recognition.

"Yes, yes. May do nicely," he seems to say to himself.

Omega's murky skyline stretches out behind them, a counterfeit horizon.

Beneath the crisp lights of the Normandy, Shepard sees more.

Mordin presses a finger to his lip and holds it there, eyes flitting about the lab. A soft hum of appreciation sounds from his throat.

"Let me know what you need," Shepard begins, "and I'll get it for you."

"No budgetary concerns. Hmm." He says it less like a question and more like a confirmation.

Shepard crosses her arms and nods. "Cerberus will provide you with anything you require, so long as you can get the job done."

Mordin tuts then, his hand falling back to his side as he pitters around the table. "Expected Cerberus' extensive funds. Did not expect generosity of such to non-human contracts." He glances back at her with little more than acknowledgement. "Still, could not ask for more challenging proposition. Excited to get to work. Will need time, Shepard. No distractions." With that, he turns from her, fingers already tapping along the terminal's keys.

She stands there in the lab's threshold for a moment after his abrupt dismissal. And then she makes her way from the room, his unexpected hum of farewell following her through the corridor.

She finds herself in the Tech Lab most days, her mug of coffee leaving a perpetual ring stain along the tabletop beside the research station. In the time between missions, she makes herself useful. It is easier to mindlessly sift through omni-tool updates and ship-wide performance reports, than to stare up at her cabin's skylight from the vast emptiness of her bed, to watch the stars drift past – the same stars she had drowned in two years past.

She rubs a hand down her face and stares blearily at the screen.

She doesn't realize it's well into the night cycle until Miranda is on her comm., checking in for her shift.

Mordin has been singing.

Shepard notices it like a sudden splinter, a prickling of awareness beneath her skin, adamantly wedging itself into her periphery.

She glances back at him, maybe for the first time, and he takes notice, lips turning up in an acknowledging smile.

"You…you sing?" Her words leave her before she has time to taste them along her tongue.

He hums his agreement, a single note of affirmation, song suddenly aborted.

Her brows narrow as she turns in her stool, one foot brought up on the lower rung. "I guess I never would have pegged you for it, all science-y and all." She wiggles her fingers with the words.

He cocks his head in question. "Strange, unfounded supposition," he says, not accusingly.

She doesn't rightly know why she had thought it, now that he comments on it.

He seems to understand, and goes back to his work, nodding. "Music, sound constructed in time. Follows patterns, often cyclical, but many dynamic factors. Must account for pitch, rhythm, structure, sonic differentiation of texture. Still –" Mordin pauses, pulls a single stiff breath through his nostrils, dark eyes focused on the terminal before him. "Offers some element of the unknown – the unquantifiable. Uniquely intriguing to the, hmm," – an amused chuckle – "'science-y' type."

Shepard blinks at him, all the stars and dark space and cold, frozen worlds of her past drifting by. Until she is staring unabashed, lungs stilled, fingers itching with a familiarity she cannot recall.

She remembers music.

But she also remembers silence – in the airless tomb of her exo-suit, the spinning, intangible whirl of stars as she drifted, grasping uselessly, the thin fissure across her helmet's visor that threatened to break into a thousand irreparable, inevitable cracks.

How even her gasp for air was soundless.

Pitch, rhythm, structure.

Miranda's impatient ping to her omni-tool breaks Shepard's focus, and then she is grasping for her mug and moving voicelessly back into the main hall, the door sliding closed behind her.

Mordin glances at the stained ring left from her coffee. He doesn't wipe it.

Shepard switches from her assault rifle to her shotgun just a fraction of a second too late. The krogan bearing down on her takes a shot to its shoulder, but it's still moving, still barreling toward her, her back to the rock, heat sink still empty, arm coming up as meager cover when her shields fail.

The krogan slams into her at half speed and then abruptly stills when a shock of ice blinds her, her already ragged armguard cracking, splintering at the elbow where a sharp, instant freeze stabs at the joint. She winces, breath knocked from her, but she has enough mind to push the frozen beast from her, releasing a shotgun blast into its face and watching it slump to the ground beneath shards of ice.

She looks right and sees the smoking barrel of Mordin's submachine rifle, iced at the edge where his Cryo Blast had burst forth.

"Bravado understandable, Shepard, but not recklessness." He cocks the reload on his rifle and steps back behind cover.

She is already honing in on the coming vorcha, but her mouth smarts with a retort too long dead. She glances at her exposed elbow, the cracked, blackened skin of frostbite suddenly jarring.

Her blood seeps between her teeth.

Mordin gently pulls the sheet back over the krogan corpse, his slender fingers whispering over the material, flies greedily hovering just above, lying in wait. He releases the sheet just past the crown of its head and they descend.

Shepard watches with dark, static eyes.

"So much waste," he murmurs – mournfully, if she thought too long about it.

Hefting her rifle to her other arm, Shepard stands with her weight on one hip. "I recall reading about your infiltration of Weyrloc Clan's agricenter."

He glances up at her, blinking stoically, but otherwise still.

Shepard attempts to clear the accusation from her voice, but she knows some taint of it has seeped in regardless. "You didn't seem so concerned with female krogan deaths then."

The sharp breath he sucks between his teeth in dismay brands her, barely discernible if she hadn't been looking for it. She doesn't look away when he stares at her.

The skin around his jaw tightens with his steady swallow. "Actions then were necessary, unavoidable. Couldn't risk rising growth of krogan birth rate, or political fallout if results of testing published. Covert operation was only viable option for continued peace." He spreads those slender, ghosting fingers along the medical bed's edge. "It had to be done."

"You had to perpetuate the lie." Her answer comes quicker than either expects.

Mordin cocks his head, lips pursed. "May judge my actions as subversive of current galactic ethics, Shepard, but cannot deny the differentiation between keeping status quo – " he hesitates, thrums a single finger in tense thought along the table, and then continues, " – between suppressing possible catastrophic power shift to entire galactic civilization and…and…" His furiously blinking eyes shift to the sheet-covered corpse, dark stains already seeping through the thin cloth. "And this," he ends on a near whisper.

Shepard watches him in expectant silence a while.

"Females at agricenter…not a vain sacrifice," he offers to her silence.

"According to you."

He looks up at her then.

Sighing, Shepard leans one palm along the table and inclines toward him, the bloodied corpse still between them, the flies still circling in their hunger. "But you still remember them, don't you?" she presses, hoping for something she can't put to words. "You still remember when you put them down."

His eyes narrow, trying to discern her intent, his hands slipping from the table edge. "Will always remember." The somberness with which he says it seems to seep into his shoulders and flood out into the air around them, until even the shadows of the room have dulled into a vague but persistent anchor at their feet.

"You know, I used to envy how easy you seemed to 'forgive and forget', how easy you made moving on seem." She motions to him with one waved finger in his direction, a casual allegation, before it curls into her palm, fist pressing back into the table.

She doesn't give much mind to the slickness beneath her knuckles, the warmth of something wet trickling over the table edge.

"But it turns out, memory's a bitch even to salarians."

She pulls from her lean and walks from him then. She doesn't wipe the blood from her gloves.

The Medbay's lights are as crisp and stark as the Tech Lab's, and for a moment, she confuses the two upon waking. Shepard blinks groggily up at the ceiling panels, her vision still inking black at the edges.

It isn't the pain that wakes her.

There's something lighter – tender even – insinuating itself into her consciousness, beneath her skin, into her bones. Until she is full of it.

Mordin's song.

She glances about the room until she sees him, tinkering with something far beyond her scope of scientific ability in a petri dish beside Chakwas' secondary terminal. She ignores the throbbing in her muscles, the tearing pain in her side.

She ignores many things these days.

Her hand goes to her ribs and her grunt of pain seems to catch his attention, because he stops humming, hands stilling over the petri dish, his omni-tool flashing closed. He turns slightly, so that he is gazing over his shoulder at her. His lip quirks upward with the subtle touch of reassurance. "Ah. Finally awake, hmm?" He turns back to his work.

"How long has it been?" Her words are like chalk on her tongue. She thinks about getting up, but the lulling effect of his presence slows her limbs. Instead, she lays still along the bed and flits her gaze back to the ceiling panels.

Mordin glances to his omni-tool, alight once more. "Four hours, thirty-seven minutes."

"The Collector ship?" she asks on a sigh.

"Not in pursuit," he answers succinctly, back still to her. "EDI can provide updates on current findings. Illusive Man still calling every hour. Doctor Chakwas refused inducing consciousness though, told him 'If it's the only sleep she ever gets aboard this ship, then I'm damn well not going to be the one to wake her from it." He chuckles then, his shoulders lifting with the sound. And then he stops, his hands hovering to a halt over his new find from the Collector ship. Glancing back at her, his mouth creases into a frown. "Do you…require her presence?" he asks hesitantly, eyes flitting over her form. He half-turns to her, arms held awkwardly at his sides, as though he is unsure.

But Shepard has never seen him unsure, and the possibility brings a small smile tugging at her lips at the sight. "No, Mordin. That's alright."

He cocks his head at her.

"Just…give me a minute." She closes her eyes and keeps her hand to her tender ribs. When she doesn't hear a response, she opens one eye to catch him standing tentatively in the same place, dark eyes on her. His lips make a tight, pursed line.

"Don't stop on my account," she tells him, settling back along the bed, eyes closing once more. After several quiet seconds, she hears him returning to work. After several seconds more, she lets out a faint whisper that is more plea than anything. "I meant your humming, too."

Another silence – this one like a clench of air in her lungs. The room is too small for such quiet, and she fears that both of them may know this.

But then, he sings. Something foreign, but steady and calm.

Pitch, rhythm, structure.

She listens to every note and doesn't fall asleep. Instead, she is blaringly awake.

Agonizingly aware.

"Oh god," she murmurs, before retching onto the grimy tile again, the stark light of Afterlife's neon sign cascading over her form as she kneels on her hands and knees off a side alley.

She can hear Mordin sigh behind her. "Warned about dubious alcoholic beverages. Did not listen."

"Oh shut up," she moans behind the curtain of her hair, fingers curling along the floor. Another wave overcomes her and she coughs up a string of bile, one hand pushing the hair away from her cheek unsuccessfully. "Just…just hold my hair, okay?"

"Hmm?"

She glances over her shoulder, eyes wet and face bursting red from the exertion. "Just hold my damn hair back, will you?" She watches him blink dumbly at her before kneeling down beside her. She leans back slightly on her haunches, knees aching from when she had dropped unceremoniously to the hard tile. She sniffs loudly, eyes rolling shut in exhaustion.

And then there is the gentle, hesitant pressure of his fingers along her scalp, pulling her dark hair cautiously from her face. Strands slip forward again, but he recaptures them easily. He almost loses his grip when she shoots forward to retch again, but he follows her down, fingers threaded in her hair.

When she is sure she is finished, she reaches a hand back and grasps shakily for his sinewy wrist. He lets her hold him there while she breathes. The heel of his weathered palm is cool at the nape of her neck.

Mordin's fingers light against the permanent ring stain left from her coffee mug along the research table. He stares at it, the pads of his fingers trailing along the stain and then to the edge of the table. He pulls a weighted, silent breath through his lungs and blinks his fathomless eyes at the ring.

Shepard comes through the door then, a soft whoosh signaling her entrance.

He glances up at her, hand falling back to his side. The grooves and marks of his rust-colored skin are apparent in the stark Normandy light.

Shepard blinks at him, standing in the threshold, hands holding two mugs before her. Her gaze flits to the coffee stain on the table, then back to him.

Somewhere off in the distance, too far for them to see this night, the Omega relay gleams in brilliant uncertainty, a threatening, red-hazed orb. Tomorrow, it will be behind them, and Shepard wonders if that will be a comfort or a menace.

"Coffee?" she offers meagerly, her hands motioning with the twin mugs in her grip, shoulders shrugging in apprehension.

Mordin scrunches the wrinkles around his nostrils in mild distaste, but he's conscious enough to try to hide the motion, instead turning to the lab's far window. "Stimulant unnecessary, Shepard, especially of such…hmm, undesirable taste."

She hides her disappointment well, a thinning smile gracing her lips. She nods – once, then twice, though not so sure – her eyes landing on the mugs. "More for me then," she says, voice low as she turns to leave.

"Coffee unwanted, but perhaps…conversation?"

His voice catches her attention before the doors can slide open before her. She pauses, glances back over her shoulder, eyes flitting over his face.

That soft, worn smile, perhaps not blatantly inviting, but subtle in its encouragement.

She walks back into the room. "I'd like that."

She likes more than that, though she does not voice it this night, nor any of the nights after when she sits and wonders at her survival, the Omega relay only a memory in the distance.

She wonders at her lasting.

It is many months before Shepard sees him again, amidst Cerberus bombardment and the secrets of Sur'Kesh. She stills, only barely, the urge to raise her palm to his cheek, to know he is real, to remind herself that some things last.

Instead, she blinks gleaming, salt-tinged eyes at him, fingers curling into her gloved palms, a vacant, disbelieving tilt of her mouth.

If she thinks too hard about it, she will realize that missing him wasn't the hardest part.

It was not knowing whether she was missed as well.

And then there is an explosion in the elevator, and she throws herself back, hitting the ground hard, hip-first, her frostbite-scarred elbow slamming into the tile. The hiss she releases in pain brings Mordin to her side instantly. When she blinks through the fog, he is tugging her up, and in the moments they re-access their exit route, Shepard focuses on the pressure of his fingers under her forearm, the slight downward lilt of his lips when he eyes her critically, gauging her condition.

But she is the first to speak. "Are you okay?"

When he sees she has no lasting damage, his eyes alight with something she might have called mischief if she had known him better.

But she knows him far less, still, than she is ever likely to be satisfied with.

"All outer extremities accounted for," he replies lightly, pausing before glancing up to indicate his shorn off horn. "Mostly," he finishes on a chuckle, glancing back down to her, releasing his hold of her arm. His smile is something singular and private.

At the same time Shepard discovers she is in love with him, she also discovers that they may not live long enough for it to matter.

When she comes to him in the Medbay, he is still leather-lined and pock-marked; she is still a cross-stitch of memory and fabrication.

"I suppose there are worse places to have found you in," she tells him, referring to their recent incursion on Sur'Kesh as she leans back on the table ledge next to him with a smirk.

Mirroring her position beside her, Mordin stares out past the Medbay windows, past where even Shepard is unsure she can follow. "Certainly can't claim conditions were 'amiable' when essentially planning subterfuge amidst colleagues but –" and here he laughs, short and rueful, his tongue holding back the sound after a second, "- reminiscent of former STG days. Dangerous, covert, stimulating. Good to be back in action." His fingers are a breath from hers along the table, though neither moves to get closer.

They share a look – maybe nostalgic, maybe content.

Quite possibly regretful if they looked any further.

Shepard tears her gaze away first, back toward the window. "You always were a risk-taker, though you'd never admit it."

"Not the only risk-taker in the room," he supplies.

She smiles then. Actually smiles. It is such a foreign feeling she doesn't know whether to laugh or wail or stay deadly, unaccusingly still.

Maybe then she could feign away this clutch of her heart.

"Some risks are worth taking," she answers, pushing off from the ledge and heading toward the door. She halts just before exiting, turning to nod at him in tender farewell.

When Mordin catches sight of the darkened, scarred patch of skin along her elbow, just below the rolled sleeve of her uniform, his throat tightens, fingers curling spastically along the table edge.

She is gone before he can open his mouth in retort, or agreement, or anything more than silence.

This silence they have each let settle between them like rust.

"Had to be me. Someone else might have gotten it wrong."

How she hates the words. How she hates even more the quiet determination with which he says them, eyes turned toward the tower, shoulders sagged with the weight of inevitable responsibility.

Around their arrested forms, the Shroud is slowly disintegrating, debris and shrapnel falling all around them. She has no time, and he has no alternative, and in the midst of all this, Shepard finds that the words she needs are simple.

"I'll keep you with me," she whispers to him amidst the fiery hail.

Somehow, he hears her. Somehow, he turns to her.

Somehow, she thinks it might be enough.

"Here," she emphasizes, one trembling, gloved fist thumping against her plated chest. "I'll keep you with me here."

Tuchanka's sun is a blaze of fire at the back of her neck, her helmet sitting forgotten on the stone steps. Embers flare around them, sand blasting her cheeks in the wind, and smoke curls around her boots, the ground quaking beneath her with a promising rumble. It reminds her that even Reapers may die.

But memory does not.

"I'll keep your memory," she breathes, stepping closer.

She knows she will never be close enough.

He grasps for her elbow, wiry, purposeful fingers anchoring her to him, curling along her armguard. It is the most desperate she has ever seen him.

He watches her with dark, unnervingly wide eyes. His lips purse, the harsh wrinkles around his mouth tightening. He dips his head down, his fingers flexing over her elbow. A sound leaves him that is somewhere between a sigh and a choke. "Only wish to have something…greater to offer…than a memory." He doesn't look at her, instead keeping his eyes trained on her shoulder, but the way his body inclines toward hers says more than either has ever put to words.

Just his proximity. Just the sureness of his touch on her arm. Just the soft exhale of his breath between them.

She releases a tremulous chuckle to mask her terror, a hand coming up to cover her mouth as she blinks back the salt-sting of tears. "Careful, Mordin. For a moment there, I was beginning to think you liked me."

"More than liked, Shepard," he mumbles. "More than a moment."

She stills, palm cupped over her mouth.

He looks up at her then, a secret, sacred smile gracing his lips. His touch along her elbow lightens, and then slides down the length of her arm, until he is grasping at her hand, stiff, slender fingers pressing against her gloved palm. He holds her there amidst the destruction for what might have been moments or might have been ages.

Neither seems quite long enough.

Another sigh, his head cocked to the side. And then his mouth – that tender, exquisite thing – opens for the last time. "Go."

She fumbles as his hand pushes her away. He steps back from her.

"Mordin," she half-moans, half-cries, breathless, aching – feverish.

He says nothing as he releases her, whisking away into the elevator and up and up and into the Shroud where she would follow if she hadn't promised him.

If she hadn't promised to keep him.

Bits of concrete rain around her, the air trembling with the explosions. She stumbles through her haze back to the vehicle, her eyes skyward.

The blaze of the Shroud's implosion isn't near as blindly as she expects.

Tuchanka's sun never seems to set.

Years later, she finds her fingers move to that scarred, dark patch of skin along her elbow when she thinks too long about the past. Because some things never leave you, and Shepard knows this lesson best.

Like an old frostbitten wound.

Like a ring stain of coffee along the Normandy's research desk.

Like his song in her bones.

Like rust. Like memory.

Sometimes when she wakes, she spreads her hand over the empty space beside her on the bed and imagines his warmth. She keeps her windows open, the red sun always at her back. She knew, before she even knew she loved him, that one day she would look for him and he would be gone.

But she keeps him, even still.

She keeps him.

Because not all things turn to rust.