Disclaimer: I own nothing but the idea which formed the story, and I make no profit from having written it. Characters within belong to Marvel.
"It wasn't worth it."
Tony looked down at his friend. They'd fought before, they'd had their differences before, but their differing opinions concerning the Registration Act had been so great it had torn them apart. It had robbed the world of Steve Rogers, it had robbed his friends of Steve Rogers. There could still be a Captain America if Bucky Barnes was convinced to take up the mantle again, but Tony didn't think he would. If anything, the ex-Soviet spy was likely to do to Tony what the Red Skull's sniper had done to Steve and Tony thought he would welcome it. Maybe he would even get a chance to apologize before being dragged into Hell.
"If I could, I would switch our places." Tony spoke quietly, his metal covered fingers absently flexing on the Iron Man helmet he held between his hands. "It was never meant to be this way, Steve. I'd take it all back if I could, I'd take the bullet if I could." He paused and closed his eyes, bowing his head. "I'd do anything, give anything to get you back."
Tony was so emotionally weary that he barely jumped at the sudden intrusion. Instead he opened his eyes and turned to look at the person who'd spoken. It had been years since he'd last heard that voice, and had indeed never expected to hear it again. He certainly wasn't sure what to think of them showing up now.
"Loki." He acknowledged him.
The Asgardian Trickster looked just about as Tony remembered him, though his hair was a little shorter and less ragged. His clothing was slightly less grandiose as well, though he'd kept with the same green, black and gold color palette. Whatever punishment he'd been suffering until this point didn't seem to have done any permanent damage, and for some reason that grated on Tony's nerves.
Loki smiled at Tony as if sensing his irritation, but the smile faded again when his eyes passed from Tony to Steve and he stepped forward to reach out and run his fingers lightly over Steve's shield.
Tony stood up quickly, dropping his helmet and Loki backed away in a smooth motion as if Tony's movement had absolutely nothing to do with his retreat.
"What do you want?" He half-growled, ready to defend his friend's body from the Asgardian if he had to.
Loki regarded him in silence from where he stood, but then he steepled his fingers and regarded Tony the way royalty may regard a common beggar, as if he was doing Tony a favor by acknowledging him and Tony's fingers curled into fists as his expression hardened.
"You said you would give anything to get him back." Loki spoke before Tony could do something rash. "Did you mean it?"
"...What if I did?" Tony challenged.
"Well," Loki nodded toward Steve. "I have some skill in necromancy. I could restore his soul to his body, but for a price of course." He looked back at Tony. "So would you really give anything?"
Tony stared at him. Make a deal with Loki for Steve's soul? He'd have to be completely out of his mind.
"...He'd be himself?" He found himself asking.
Loki smiled. "He would be himself. Soul, memories, mind and morals intact."
Tony eyed him warily. "You swear it?"
Loki put a hand over where Tony supposed his heart would be if he was human. "I swear."
Tony chewed on his bottom lip. What was a trickster's word worth? "Why?" He asked. "Why would you do me or him any favors?"
"Because you said you'd give anything." Loki responded.
"So what's the price then?"
"A soul for a soul, Anthony."
Tony bristled at being called by his full first name, but then he sighed heavily and finally relaxed his hands. "So I die and he comes back?" He could accept that, even if it meant his soul was going to be in Loki's hands.
Loki's smile turned malicious. "Oh no." He said. "You'd get to live your life out fully, or however fully someone in your profession can live. When you die however, I'll be waiting and you'll be mine."
"A deal with the Devil." Tony smiled mirthlessly. "Do I have to sign in blood or something?"
The Asgardian laughed, and Tony felt chilled. "So it is agreed, then? Your soul for his?"
Tony looked to his friend's body lying there and he reached out to touch his shield. Steve was worth more than Tony was. More than ten, twenty, a hundred times Tony's worth. His soul wasn't worth much, but the world needed Captain America.
"Yeah." He said, looking down at his friend's death slack face. "You've got yourself a deal."