FIC: eternal flame (MCU, Bruce/Natasha, PG)

[carlyinrome]

I tried rewriting. It's so different, and not organic or lovely at all. I'm so sad.

For posterity:

For the graduation ceremony, there is an IV. Natasha has had medicine before, antiseptics and ointments for injuries, but never a drug that squirms inside her body, pushed through her tissues by the beat of her heart.

The nurse inches the thick needle into her vein, and Natasha feels the medicine burn up her arm. Her chest fills with warmth as the drug engulfs her heart.

***

Bruce has frostbite. The impact of a shell exploding at the Other Guy's feet knocked him unconscious; Bruce had returned to himself, fragile human flesh packed in brittle snow. It is Eastern Europe in winter, and it is bitter cold.

SHIELD has outposts all over. They find one straddling the border of two 'stans, and debrief.

Natasha takes Bruce into the quarters in the back. The room is warm, the light soft. From the other room, the speech of their brothers in arms becomes formless, all rhythm.

Natasha presses rags soaked in hot water to the red and white blotches on Bruce's shoulders, hands, cheek.

"I'm sorry," she says. "I should have kept a better eye on you."

Bruce smiles his near invisible smile. Her eyes are now trained to parse his body language, but she can also hear his emotions in the timbre of his voice.

"You had more pressing matters," he says.

Natasha turns her head in a sharp nod to flip back the red coils of her hair from her eyes. She makes fists around the cloth, wringing the water from it. The pads of her fingers have begun to pucker.

Natasha studies the worst patch of frostbite, waxy blisters on his shoulder. She presses her fingers to it gently.

"It's looking better," she says. "How does it feel?"

"Like I'm thawing."

Natasha dips the cloth into the water. Rivulets course down her arms; her flesh is heated from handling the hot water, but Bruce's skin is still so cold. She holds the cloth against it longer, harder

Natasha has always thought of ice melting as something being lost. The form of the ice degrades, dripping away.

Sometimes when Bruce's mind is forming a solution, he talks out the variables, the formulas, the processes. Natasha will sit in his lab listening as he works through equations and comes to conclusions.

Once, he spoke to her about phase change. Solid to liquid, liquid to gas--nothing is lost, only transferred. Molecules rearrange themselves; chemicals react. Energy is never created or destroyed, and the universe today is made up of the same parts as it always was, just in different configurations.

Natasha presses the heel of her palm against the rag, urging the hot water into the cells of Bruce's skin. In reaction--because there is always a reaction--Bruce lays his hand across hers, adding to the pressure.

Natasha feels heat flood her chest. She nearly demurs, but she's never been one to flinch, so she holds his gaze.

“Does it hurt?” she asks.

His voice is low, slightly rough. “That's not a word I'd use, no.”

Not so long ago, nothing penetrated her heart but adrenaline as her hand ended a life. The thrill of the kill. Because a perfect execution does make the heart beat faster. The ballerinas rising to pointe, their movements pure muscle and skill, defiance of gravity. She could have been a dancer.

Emotions are messy. Weapons are precise. There is no room for heart in this game.

But it's not her game anymore.

Natasha burns like magnesium: brilliantly, powerfully, a reaction that will continue strong until acted upon by an outside force. Phase change; nothing is lost, only rearranged. It's not surrender, only energy transfer. She gives some of her power to Bruce, but she receives something equal in return.

She is heady. There's not enough air, she can't take a deep enough breath with her fevered heart pumping chemicals through her brain. It's not a drug, because a drug is administered, and this comes from within her.

Bruce squeezes his fingers over hers. His other hand slides around her hip, settling at the small of her back. Gentle pressure, pushing her body towards him by inches. It's a question, an offer. Bruce in this state doesn't act without thought. Natasha does. Her body is faster than her brain, fueled by muscle memory and the precision of a honed skill. Ballerinas cannot rise to pointe overnight; it takes years of practice, the shape of the muscles in the feet conforming to the act.

It's taken her heart time to remodel. She bows her head toward him; they breathe the same air, taking into their lungs molecules that were stardust as the universe began. Natasha closes her eyes as they kiss. It's not a surrender, only a chemical reaction.

Natasha burns like magnesium. She feels herself pulled, as the sedatives at her graduation ceremony pulled her toward sleep. There's no way to resist, and she doesn't want to. She puts her hands on him, feels his flesh against hers. He is warm, finally.