(A/N: I still don't own the Avengers and I never will. This is a slash fic and so I don't want you to read it if you can't handle that fact. Here we have a Steve/Loki fic because I just haven't done one of those by themselves yet. Does contain mentions of Thor being an overprotective older brother, Clint and Natasha being overgrown children, and Tony and Bruce as science bros. It does also contain a decent bit of mention of blood and injuries so if that makes you twitchy…also needles.)

Flutters like a Rabbit Heart

Tony had just come up from the lab; Bruce was at his back, which was good because Bruce was strong enough to catch the billionaire when he fell back in shock. He allowed himself to be pressed against that solid chest for a moment while his genius brain struggled to process what he was seeing. Thor stood in the middle of the living room his large arms supporting the half conscious form of Loki. No one had heard from either God since the incident in Manhattan and Tony wasn't sure how Thor even found the tower. But then Thor spotted Tony and electric blue eyes were full of fear and concern.

"Thor, what's going on?" Tony choked out as he finally made his way toward the two brothers. Loki's feet may have been on the ground but it was obvious from the bend of his knees that he was unable to support himself. The dark-haired God looked broken, as if someone had recently picked him up and crumpled him like a piece of paper. There was a line of blood coming from somewhere behind his hairline and his pale lips were broken and bruised. They couldn't see his eyes but Tony suspected that they weren't quite open.

"I had to bring him here. I know that he was your enemy Stark and Green One, but he is not anymore and he needs help. Asgard was not kind to him, he is…my brother is mortal…please, I know not if these wounds are fatal. Odin has taken the price of human life from my brother's flesh and soul," Thor was crying against Loki's head as he lifted his brother gingerly into his arms.

"Taken it from his flesh…mortal? JARVIS alert the rest of the team. Thor follow me, we have a hospital room here," Tony said and turned to find Bruce already leading the way. Between the two of them they had earned a medical degree in the last few months, but Bruce was more adept at the fixing stuff part of the equation while Tony was better at damage assessment. Thor followed as quickly as he could with Loki in his arms screaming in pain as he was jostled into an elevator.

The elevators were barely closed when Tony tore open Loki's shirt, a normal human button-down number that Tony would replace later. Loki's flesh was literally torn open, wounds so deep that bones were visible in places. Tony grew sick to realize that the shirt Loki was wearing had originally been blue and his hands were slicked with blood where he had touched it. Unsure of how he had missed it before he uncaringly relieved the former God of his belt and shucked his pants. It was worse than he had imagined. Loki was utterly mangled.

"Tony, I need you clear-headed on this one," Bruce said and Tony swallowed thickly, nodding as best he could as they piled out of the elevator. Loki's blood sodden clothes were left behind as they rushed him to a steel table, the best they had for triage.

"I count at least 60 deep wounds varying in length from one inch to roughly seven inches. Bruising is widespread and indeterminately serious. Possible broken jaw, three teeth need to be reset and there seems to be surface damage to the scalp. No concussion. Left pinky toe is absent," there Tony gagged, "Wounds on back, possibly from flogging, have begun to fester," Tony ran down the list as he spotted injuries and Thor clung to Loki's hands for they were the only things not damaged.

"Tony…oh Jesus," Steve's voice cracked and he dropped the clothing that he picked up. He raced over to where Loki, though naked and covered in unimaginable injuries, was trying to convince the Avengers to stop helping him. Bruce looked up at the Captain and gave a grim nod.

"Steve, I need you to take his ankles, no matter how much he fights, don't let him go. Thor, hold his wrists down," Bruce commanded and cleared Tony away to get the supplies they would need. The physicist turned medic began with cleaning every wound that he could find. Loki screamed piteously and shrieked his misery to the Gods, the look on Thor's face told them all that no one was listening.

Clint and Natasha showed up when Bruce had begun to stitch the wounds shut, after monitors had already been hooked up. Clint tried, really tried to be satisfied by what he was seeing, but he couldn't be. He and Natasha were an extra pair of hands each that were fully capable of stitching a wound closed and so they sterilized their hands, donned gloves and grabbed needles from the tray Tony brought them.

It was slow, agonizing work and as they went it because obvious that Loki had lost too much blood. They watched his pulse climb higher and higher as they worked, even with painkillers flooding his system to keep it down. Tony understood this and broke out a transfusion kit without saying a word.

"He needs blood," Tony said as he held up the kit, his gloved hands shaking slightly from muted panic.

"Then he shall have mine," Thor stated and began to take his hands away from Loki's wrists.

"No, your blood will kill him Thor. Steve, yours is universal right? We have to move to his legs soon anyway. Go with Tony," Bruce said firmly and Natasha gave Steve a slight push toward the blood bag and the needle in Tony's hand. The red head was in his spot at once, seeing to the missing toe that no one had felt comfortable dealing with. Steve was not afraid of needles, but he also knew that his blood was not normal blood; it could just as easily kill Loki as help him. They had no choice though and so he sat and swabbed his own arm and flexed until a vein stood out ready for the needle.

He gritted his teeth as he felt the sharp metal tear and slice through his flesh and the blood begin to flow entirely too slowly. Loki was still screaming on the table and Thor was weeping at the pain Loki was enduring.

Once the bag had filled Steve removed the needle and pressed gauze against the wound, waving Tony away to begin the drip into Loki's body. The bag joined the IV stand and Steve watched as he blood drained into the former God's body and he hoped, he prayed that it would work.

The night wore on and Steve gave up two more pints of blood, not at all caring that he was going to suffer for it later on. He had been relegated to sitting and waiting for someone to swoop back in for blood. Loki had fallen unconscious and his pulse remained high, but as far as Tony or Bruce could tell it was more normal than before. And when they were all done Steve brought down a set of clothes which he helped Thor to dress Loki in.

They moved Loki to a bed and each of the Avengers took one of the hospital beds to catch a few hours of sleep while still being close to keep an eye on Loki. Steve watched the dark haired man with interest; he was unable to sleep but was able to fill the time with laying the mask of Loki's healthy features over the ones he wore now. It was hard to ignore the fact that even damaged, Loki was a beautiful man. Not handsome, not dapper or debonair, but beautiful, pretty, soft almost. Steve wanted to touch that pale skin and chase the bruises away until it resembled what he had once known his enemy to wear. Even though Loki was no longer his enemy, Steve was torn by these feelings, he didn't know if was allowed to think such things about another man.

"You seem distressed Captain," Thor's voice was soft and Steve wondered when the God of Thunder had come to stand by Loki's side. Steve looked up into eyes bluer than his own and tried to find his voice.

"I would say that I am," Steve whispered, ashamed as his eyes left Thor's to look once more at Loki.

"Surely you can tell me," Thor said it soothingly, his fingers slowly sliding through Loki's newly washed hair. Steve figured that the man that Loki once was would have been glad that his head wound had not required sacrificing his hair.

"I don't think that I know myself. I've never experienced this before. Your brother is a beautiful man Thor, and that confuses me," Steve whispered, mouth and throat going dry as his eyes continued to avoid Thor's gaze.

"He has broken many hearts Captain. My brother is, was, the most beautiful man in Asgard. You should not be ashamed for he has brought many a God to his knees with his looks alone. But Loki is human now and so fragile that I fear to touch him. Your blood will grant him some measure of strength and for that I can never thank you enough," Thor's fingers trembled as he withdrew them from Loki's hair. The larger blonde looked carefully at Steve. "You would never hurt him, would you Captain?" the God whispered.

"I would never hurt anyone if I didn't have to. Why do you ask?" Steve responded, eyes curious and afraid. Thor's lips drew into a sad smile, his gaze shifting briefly to Loki's still form.

"I ask because you gave him your blood. For my people that is a sign of undying love and commitment. I doubt that Loki would view it as such, the situation was dire after all and he did not request it. But your blood in his veins marks him as yours," Thor explained softly and Steve felt his heart suddenly kick into high gear. He would go and effectively marry an alien. That was so like him.

"Hush brother, I do not seek to call him on the offer that he has made. Much as I might wish it, I am no longer fit to be any one's spouse," Loki's voice was brittle and frail and Steve was at his side nearly as quickly as Thor was. Gem bright green eyes smiled weakly at the pair.

"How do you feel brother?" Thor asked and Steve couldn't help but grasp Loki's hand to check his pulse for himself.

"It flutters like a rabbit heart does it not Captain? I can feel it thumping away in my chest. Your blood is strange and potent. I can feel some wounds healing already," Loki said, fingers briefly grasping Steve's hand. He did not look disappointed when the Captain was too shocked to return the grip.

"I wouldn't entirely mind if you did take me up on that offer," Steve whispered gently, checking that as many of the wounds that he could see were still properly bandaged. He blushed as he realized what he had said; back when he was a kid he had crushed a lot of those urges, knowing that they weren't right. But with Loki so close, knowing that there was some mutual attraction at least, it was hard to be in that mindset again. He wanted to touch Loki's skin and kiss Loki's lips, and he didn't quite care if he was damned for it.

"Brother, you are still weak, you should rest," Thor breathed, his thumb lightly tracing Loki's jaw, which thankfully had simply turned out to be heavily bruised instead of broken.

"I doubt that I could. I'm so cold Thor," Loki said quietly and it was true, his skin was quite chilly. The blanket and Steve's clothes didn't seem to be doing much for it. Steve knew that Loki needed to sleep and knew that he himself was always the warmest person in any room. It seemed logical to climb into the bed with Loki to share his warmth and the former God seemed to appreciate it greatly. Thor retrieved the blanket from Steve's bed and threw it over both men with a whispered good night.

"You will be warm now," Steve said gently and allowed Loki to find a comfortable and safe way to curl closer.

"You give me your blood, you clothe me, and you offer me your own flesh for warmth. Captain you do know how to make a girl blush," Loki whispered softly and Steve rolled his eyes, leaning in to kiss those lips so that Loki might be silent. He was pleasantly surprised when the kiss was returned. So that was it then, he had just entered into a relationship with a former super villain. Yep, the ice definitely messed up something in his head. And he was glad for that honestly. It was easy to fall asleep holding onto Loki, and so he did.

He woke up to the sound of a camera shutter and the sound of Clint and Natasha's laughter. Steve cracked an eye to see Clint nearly bent double, supporting Natasha who was also falling over, both were laughing so hard they were crying. Tony and Bruce were checking on Loki's wounds, which it seemed were well on their way to healed. When Loki woke a few minutes later and kissed Steve good morning there was a simultaneous 'Eew, gross' from Clint and Natasha's direction followed by more giggling. Neither Tony nor Bruce batted an eyelash at the action.

"How's he doing this morning?" Steve asked as Loki was made to disengage his arms from around Steve's body. Tony and Bruce both smiled.

"Pretty good actually. It's going to scar and he will be bruised up for weeks, but your blood was good enough to heal him rapidly. Stitches won't be out for another week, but injuries like this should have taken much much longer," Bruce said his eyes fixed on the still giggling pair of assassins. It really was unbecoming.

"Care to explain how you got in there with him? Or for that matter why Thor didn't cave your skull in?" Tony asked with a raised eyebrow as he looked down the bed to where Thor stood watching. Loki grumbled and pressed his lips firmly to Steve's until the blonde kissed back.

"The Captain is a suitable partner for my brother. They have accepted each other, I see no reason to protest," the Thunder God said plainly and for some reason that was the last that Clint's knees could handle and when he went down Natasha went with him, the cellphone on which she had captured the image of Steve and Loki slid across the floor and became Tony's. Loki only let go of Steve long enough for the exam to finish and then he was back soaking up the Super Soldier's warmth and drifting off to sleep once again.

(A/N: So that was my first real foray into this particular pairing. I hope that it was satisfactory. Let me know what you thought.)