Warnings: rape/non-con (both male-on-male and female-on-male), Loki-whump, massive changes to canon movie, possible OOC-ness from Loki, intentional OOC-ness from some others.

(About slash: my own opinion is that slash relationships are between two consenting parties. Therefore, I'll go ahead and say there's no slash in this story. There's no het romance, either.)

Disclaimer: I don't own The Avengers or any of the characters therein, I'm only butchering that wonderful movie for fun and being mean to Loki (because my evilness knows no bounds *insert maniacal laugh here*).

A/N: Have you ever read an Omegaverse story? Well, this isn't one, but it sure is close. No alphas or betas or omegas, at least not in name. This story is basically a re-write of The Avengers, a "what-if" scenario. Like, "What if Loki went into heat every few hundred years and what if that had happened right in the middle of the movie?" Sadly for Loki, he's an omega and everyone else is alphas or betas. Earth is completely unchanged (I don't like the necessary socio-biological changes to history that Omegaverse fics have to add for it to make sense), I've only messed with Jotunheim's culture, which we won't be seeing here.

As I always say: don't like, don't read. May disturb you, please read warnings before proceeding.

The Unopened Door - Chapter 1

The blast pushed Loki back onto the steps behind him, the kinetic force was strong, but his magic kept him intact - although it still hurt.

"Make a move, reindeer games," said a mechanized voice behind the red and gold flying armor, arms up, ready for another attack should Loki move.

Ah, the Iron Man, Loki thought, amused. Barton had told him everything. He had nothing to fear from these so-called heroes. Even so, he didn't wish to be hit again, and anyway, all was going according to plan.

So Loki raised both arms in surrender, still wary but certain the Hawk's words would prove true, that the heroes of SHIELD wouldn't harm him if he surrendered to their custody.

X - X

The two mortals spoke incessantly after they entered the flying vehicle, especially the man of iron. Loki had very little use for idle mortal conversation yet he listened, there was no such thing as useless information, not to say information couldn't be boring.

The Iron Man especially - Tony Stark - was prone to inane prattle, and the captain often appeared as confused as Loki by some of the armored man's words.

Although the god of mischief listened to the mortals, he was slowly becoming aware of a strange sensation growing in his chest; a warm kind of purring. He adjusted his weight on the seat and frowned. What could it be? Surely neither mortal has injured me terribly... He squirmed a little, trying to get a feel for whatever this odd feeling was, which was getting stronger by the minute.

"Hey, you okay?" asked the man out of time suddenly.

Loki paid him no heed, still trying to figure out the sensation. He shook his head, annoyed that anything might possibly interfere with his plans. No... everything is going so well. What is this?!

He suddenly felt a pain at the back of his head and his hand jerked up to cradle it. It wasn't his intention to show weakness, but the pain was so unexpected he couldn't help the involuntary motion.

The blonde mortal neared. "Woah, what's wrong? You don't look so good."

"He looks fine to me," said the Iron Man. A glance at him showed a strange smirk; an odd look in his eye.

The captain, Steve Rogers, stood bent over slightly, worried expression on his face. "He's not fine, Stark. Hey," a fingertip on Loki's shoulder for a moment, then it was gone, "are you okay?"

Loki furrowed his brow and stared at the floor as the pain in his head began to subside. He nodded absent-mindedly. Why would the mortal care?

Unfortunately, the warm feeling in his chest, while slightly subdued, hadn't gone away completely. It hummed in his core, like a slow-burning fire that didn't seem likely to go out anytime soon.

Rogers was still leaned over, close to him.

"Cap," said the other mortal, "why don't you step back?" Oddly, the comment sounded less like concern and more like warning. But a warning against who?

A glance at the Iron Man showed him staring - almost glaring - at the captain.

"Stark?" asked Rogers. His voice was laced with concern, clearly he was just as confused by his comrade's behavior as Loki.

"I said," intoned Stark, walking closer, "step away from him." And now it was clear that the warning was for Rogers, against Stark himself.

Loki's confusion grew; Rogers' clearly was, too.

"Tony-"

"Are you deaf? Because I really hate repeating myself. What? Frozen seawater still stuck in your ears?"

Rogers scoffed, confusion mixed with indignity. "What's gotten into you, Stark?" Even so, the captain stepped away from Loki, apparently not wanting a confrontation with his fellow mortal.

A female voice called from the front, "What's going on back there?"

"Nothing," answered Stark immediately, voice flat. The mortal then walked toward the god, eyes fixed on Rogers. "You just stay the hell away from him, captain."

"What?" said Rogers in exasperation.

When the Iron Man reached Loki, he knelt and finally broke his gaze on the other mortal. To the god he said: "Don't mind him, he's been frozen too long; brain damage or something, probably." The words sounded like a jest, but his tone didn't.

"He-" began Loki, baffled about both what was happening to him, and to the two mortals. "He did nothing to me..."

"Oh?" Stark leaned closer. "Well that's good. You need anything, anything at all, you just ask me. Tony Stark," he winked, "at your service."

Loki's eyes were wide with his brow furrowed, staring at the mortal. He leaned back when the mortal leaned in more. What is he doing-?

"Stark?" asked the captain, voice firm, but the mortal before Loki didn't seem to hear him.

All at once it hit him; Loki knew what this was - what it could be. But it can't be! His eyes blew wider, suddenly he didn't see the man before him, too caught up in this new possibility. No, no, no... it's not... It can't be! Not now! Please not now... His eyes darted around, thinking. He put the pieces together; the warm feeling in his chest, the splitting headache that dissipated quickly, the mortal's strange behavior. He shut his eyes tight and lowered his head. No...

He opened his eyes and flinched when he heard the other mortal yell, "Stark!" a hand on his comrade's shoulder. "What the hell are you doing?!"

"What's it to you?" said Stark angrily, straightening up. He stood in front of Loki, as if blocking him from the other's view. "You think you can do better than me, huh?" He jabbed a finger into the captain's chest. "He's mine," growled Iron Man.

"What?" the captain's surprised look matched Loki's, except for different reasons; Loki knew why the armored mortal was acting this way.

Oh no, please, not now... not now- why now?! He had a mission to complete, I can't... I can't deal with this now! And what effect would it have on the mortals, anyway? So far the man of iron's reaction was what was expected - but why did the captain seem unaffected so far?

"You heard me," growled out Stark.

A flash of light distracted everyone a moment. Loki heard the woman - Natasha Romanoff - mumble something while they all stared out the windows. Lightning... It clicked immediately. Thor!

Stark turned around to face the god. "Hey," he said, an armored hand on the side of Loki's face. "You okay? Is the storm scaring you?" The god was still too surprised by everything to acknowledge the hand on his face. Thor... Thor is coming.

Something thunked on the top of the flying vehicle. The Iron Man cursed and put on his helmet.

Thor is here.

X - X

The crash landing jarred Loki to his bones. Why must Thor always throw me about? He couldn't count the amount of times his once-brother had injured him, presumably by accident, whilst transporting Loki by flight - and most of the time without first consulting the mischief god.

He didn't exactly expect Thor to be gentle, but some consideration for his brother - former or not - surely couldn't be too much trouble for the thunderer.

As quickly as he could - which was not quick at all - Loki stumbled to his feet and walked toward Thor.

"Thor," he began, but the look in the thunder god's eyes, of irritation bordering on wrath, gave him pause. But only for a moment. "Thor," he started again, "I know you're angry with me, but you have to-"

"I am in no mood for your games, Loki; tell me where the Tesseract is and we may leave this world. You-"

"Leave?" Loki asked, incredulous. "And go where? Back to Asgard? Back to my family? No, I have no home." Why am I speaking of this now? I have no time for-

"If that is true then you have made it so." Thor dropped Mjolnir and walked toward him with a purpose.

"Thor, wait," Loki held up both hands placatingly. Despite his overwhelming desire to verbally spar with his not-brother, he had far more important things to worry about right now.

"For what? For you to use the Tesseract for your own ends? Or is it another's will you-"

"Please, stop speaking for just a moment?" Loki said as delicately as he could. Unfortunately it seemed to have the opposite effect he was intending as Thor stepped forward and grabbed his shoulders; Loki would have stepped back if there were not a cliff right behind him.

"Then speak if you have something to say!" boomed Thor, obviously not happy to be so interrupted.

The two stared at each other for a silent moment, then Loki finally blurted out: "I'm in heat."

A/N: So what did you guys think? Most chapters will be longer than this, so this is maybe more of a prologue. I've already written most of this story so updates should be fairly consistent, except maybe when we get toward the end as I've yet to write the last few chapters (I want to see people's reactions before I write the ending). This should also mean it won't interfere with my writing Hollow Skies, so fans of that fic, don't worry! ^^