(A/N)- Crossposted from Tumblr. Anon requested the "Soulmates AU" for Slaine/Asseylum from an AU prompt meme I did.

I took the opportunity to write Aldnoah fixfic because of course I did. Title is a reference to Dragonheart.

Enjoy!

Disclaimer: Hello new readers, I have a tradition of doing funny disclaimers at the beginning of my chapters. You'll get used to 'em. Where was I? Oh yes. Unfortunately I do not own , because you can bet if I did I wouldn't have written half the bullshit they did. Yes I'm still bitter.

Half My Heart To Make You Whole

It was a tightly kept secret on Vers just what Aldnoah did when it recognized Rayregalia Vers Rayvers, first emperor of Mars, as its rightful heir, and chose him to inherit the power to activate it.

For lack of a better word to describe it, her grandfather had told her, Aldnoah was alive. It was a living force, the transcendence of physical form achieved through advanced science by ancient Versians, thousands and thousands of years ago. So when he'd made contact for the first time, not only had Aldnoah encoded its activation factor into his genome, but it had granted him a portion of its own life force. Its Ea, he said it was called. Asseylum had interrupted then, and asked him how he knew the name. Her grandfather had just shrugged.

He didn't know what—or who—was behind Aldnoah's energy, just that it had accepted him as its own, shared half of itself with him, and would be connected to him always.

A wide-eyed Asseylum had pressed, "Do I have Ea?"

Yes, he'd told her. She did. But unlike the activation factor, Ea could not be transferred through body fluids. Ea only passed to another person two ways: Through genetic inheritance, or through the conscious, deliberate choice to grant it to someone else.

"You must not share your Ea with anyone," he'd warned her. "At least not until you take the throne, and are ready for a husband." Anticipating her questions he explained, "It can only be given once. It will bond you to that person, permanently. You will share a telepathic link that lets you sense when the other is near, feel what they are feeling, share each other's pain."

"Can you feel Aldnoah?" she'd breathed excitedly.

A warm smile touched his face. "I do. It's happy. It thinks you'll be a wonderful Empress someday."

Still, he'd warned her, she must be careful. She could not, must not, share the secret of Ea with anyone, and she was not to give it to anyone who had not first proved himself worthy.

She knew that. She knew all of that.

But she when she saw the face of that Terran boy, his blue-green eyes dull, his hair matted and lifeless, saw him struggling to breathe and coughing out fluids… she didn't even hesitate.

Maybe she had been too young and impetuous. Maybe she didn't realize what she was doing.

All she knew was that he was dying, and she wanted him to live.

Her lips pressed fervently into his, as she sucked the fluids out of him. Live, she begged. Don't die. She willed her own life into his and felt a warmth flush between them. Suddenly she felt his mind stir, sensed him coming to. She stepped back, holding her breath, waiting to see if he was all right.

His eyes opened. Happiness and wonder assailed her senses, mixing with confusion, awe, amazement… a cocktail of emotions more exhilarating than drugs. She felt his heartbeat, his breathing, his thoughts… He was alive inside her as well as in front of her.

She smiled in relief, her joy a palpable thing.

But when he had been rolled in on his chair, rushing to see the crash, her grandfather had stiffened and stared at her in horror.

"What have you done?" he whispered. He gripped the handles of his chair, squeezing them with tight fingers as Asseylum shrunk back in shame and he repeated, "What have you done?"

-AZ-

In hindsight, it had been unfair to him. Cruel even. To tie his heart so closely to hers, foist a bond like that upon him, a connection so compelling and strong it overpowered him and he didn't even understand why. It overwhelmed him, sent him into a confusion, made him feel things he couldn't comprehend.

She had ruined him the moment he'd opened his eyes.

"He will be tethered to you forever," her grandfather had scolded her. "Do you understand? As long as that boy lives he will be drawn to you. He will never be able to have a life without you. And he doesn't know why he feels that way. He cannot know. And he cannot be with you. You are a princess. He is a Terran. Do you realize what that will do to him?"

She sniffled, wiping her eyes. "Yes Grandfather," she strained softly.

He forbade her from telling him about Ea. He made her promise to marry a proper Martian noble.

And then, in a grudging show of mercy, he allowed Slaine Troyard to become Asseylum's tutor and personal escort.

If it was torturous for the Terran, it was agony for the Versian princess. Asseylum ached with the happiness of being around him, and the despair of knowing she could not have him, that she must keep her feelings locked up inside and never let him know that he held part of her very soul. She wondered how much he could tell she was in pain. Slaine never seemed terribly concerned with himself, and the rush of confusing things he must be feeling, always worrying about her instead. She wished he wouldn't. She soon became a very good actress, always masking things behind a smile and a dozen questions about Earth. She didn't want to hurt him.

He must always believe she was happy. He must never think he was upsetting her by being so eager, so loyal, so wonderful that she cursed the day she'd met him.

In time, the pain of being near him dulled. Asseylum was content just to know he was there, to always have him near. She sought him out when she was feeling lonely, curling up into his arms while he sat in dazed confusion. She looked for excuses to talk to him. She snuck out of royal functions just to see him. She clung to every moment she could have with him, cherishing it like a precious treasure.

It was with no small amount of nervousness that she departed on the shuttle to Earth, Slaine's necklace clutched tight in her hands.

She brushed her fingers on the pendant's smooth surface, willing her jitters to calm.

It's just for a little while, she told herself. We'll only be apart a short time.

She sighed, looking out the window up at the landing castle, growing steadily smaller as the distance between them increased.

-AZ-

Slaine watched the replay of the footage in horror. The car flipping over. The missile streaking towards her. Her vanishing in a flash of yellow and white.

"Asseylum…" he breathed, his hands gripping the back of the chair.

It couldn't be… It's not possible… It's not… She wasn't…

He barely heard what the other crew members were doing around him, transfixed to the spot by a paralyzing sensation and a cold heavy feeling inside his chest.

Asseylum couldn't be dead. He… he would know. He would feel it.

He backed away from the monitor, inhaling a steely breath.

That's right… If the princess was dead he would surely know it. There was something amiss at play here. Things were surely not as they seemed.

Slaine mulled things over in his head a moment, wrestling with his impulses. Finally he straightened his back, marching over to Count Cruhteo resolutely.

"Milord," he called, clicking his heels.

Cruhteo paid him a brief glance of barely-hidden contempt. "Don't bother me right now, Terran. Can't you see I'm busy trying to avenge our princess?"

"Asseylum Vers Allusia is not dead," Slaine declared.

The Count turned his head, raising an eyebrow. "Oh? What makes you say that? You saw it with your own eyes. The Terran scum killed her."

"Nevertheless," Slaine countered, "I do not believe she has perished."

Cruhteo sneered. "And why's that?"

Slaine was unable to meet the Count's gaze, looking away uncomfortably.

"Am I supposed to waste precious time and resources, just because of a feeling of yours?"

The boy dropped his chin, defeated. "No Milord."

The Count looked down his nose at him a moment longer, then dismissed him with a wave. "Get back to your post, Terran," he ordered.

"Sir!" Slaine acknowledged, clicking his heels again before he quickly left the Count's audience.

He let his anxiety show only once he was safely ensconced in the cockpit of the Sky Carrier. Slaine let out a shuddering breath, gripping the controls tightly.

If Cruhteo wouldn't believe him, he would just have to find her on his own.

It wasn't long before he was staring, gap-jawed, with disbelieving eyes through the binoculars as the camouflage flashed and popped in a rainbow of colors, revealing the familiar form of the princess underneath, alive and unharmed.

His heart gave a leap upon seeing her.

I knew it.

-AZ-

From time to time, when she wasn't busy running from her people's own Kataphrakts, or fearing for her life among the angry, discontent Terrans, Asseylum could feel Slaine's presence as a distant flicker, a beacon of comfort coming to her from across the miles between them.

She took shelter in that feeling, in the knowledge that he was okay, that he was alive and unhurt and determined. If Slaine was safe, she could endure things.

She had to believe she could make it back to him. She already felt so empty, separated from her other half like this for so long.

So she was determined to help the Terrans as best she could.

Finding a prototype battleship with a working Aldnoah Drive was a surprise, but Asseylum stepped into her royal role and resolutely activated it. Feeling it thrum to life beneath her and lift off the ground was a thrill she'd never expected.

Even more unexpected was the sudden, startling clarity of a presence.

Asseylum had had her eyes closed, but she opened them with a gasp. Her chin jerked up and she looked through the window just in time to see a Sky Carrier fly past, Inaho's orange training Kataphrakt nestled in its launching hook.

Not just any Sky Carrier. His. He was here. He was here!

Her heart was somersaulting. She was so happy she couldn't breathe.

Slaine!

-AZ-

He couldn't see her through the windows of the strange craft. Couldn't hear her voice. But he'd know that warmth in his mind anywhere.

He turned in his seat, overjoyed.

"I've found you!" he exclaimed, heedless of the listening ears. "Princess Asseylum!"

Asseylum had rushed to the window once Femieanne's Kataphrakt had been destroyed, straining her eyes for a glimpse of the Sky Carrier.

There! She could see it silhouetted against the sunrise, Slaine's heart beating steadily from it. Asseylum was too happy he was there, so close to seeing her, that she missed the creeping suspicion that traced through him.

The shock as Inaho fired a round into his engine hit them both. Asseylum felt her joy turn into hysteria as the Sky Carrier fell from the air.

"No!" she cried, rushing to the comm station. It was familiar enough to Versian controls that she found the button quickly, and opened the channel at once. "Inaho-san, stop!" she begged. "Don't shoot!"

His Kataphrakt had been moving to jump off from the launching hook, but at her words, he hesitated.

"He knew you were alive," came his confused monotone over the channel. "He could be our enemy."

"You idiot!" The sound of Slaine's voice, however irritated, sent a happy jolt through her body. "I'm not—"

"No! I know who it is!" Asseylum interrupted. "He's my—"

She cut herself off, just shy of spilling her true feelings out, growing acutely aware of everyone eyes watching her.

"He's… he's… my precious friend," she stammered out instead, feeling a flush creep through her face. She regained her composure, shaking herself. "It's my escort, and my loyal bodyguard. Slaine Troyard, a Terran. And he'd never hurt me."

She could hear the outbursts of bewilderment from behind her, and also from over the comm.

"Whaaaat?" exclaimed Inko. "A Terran?! In a Martian Sky Carrier?!"

There was a yelp from Slaine as the Carrier plunged. Inaho leapt clear, making it to the safety of the dock and letting the airship drop in the ocean and disappear with a splash.

Asseylum wrung her hands in front of her with a cry. "Please Inaho! We have to go back for him! You have to get him out of there! He doesn't… he's afraid…"

Of drowning, her mind finished, helpless to stop the clawing fear and paralyzing dread that passed between them. She tried to project calm and reassurance to him through her thoughts, but Slaine was too panicky. He had always hated water, ever since the crash.

Inaho hesitated for another agonizing moment, apparently making his analysis of the situation.

Then with a sigh he shot his grapple line into the water and went to retrieve the pilot he had just shot down moments earlier.

-AZ-

He sputtered indignantly the whole time the orange Kataphrakt fished him out of the ocean, continued to glare at the thing's pilot as he was dumped onto the hanger floor of the strange Terran/Versian battleship hybrid.

But he forgot everything when he saw her running towards him, tears brimming in her green eyes.

She flung her arms around him, nearly knocking him over. Slaine grunted with surprise, automatically flinching and anticipating a round of scathing glares, but when he looked around the other Terrans seemed just as confused as he was.

Asseylum buried her face in his front, wet stains gathering in the fabric.

"I'm—I'm so happy—so glad you're okay!" she strained out between sobs.

Her heart was beating rapidly, breathing erratic. But there was an overwhelming sense of relief. Of an end to a long worry. A strange sense that… things were complete again.

He relaxed, letting his arms fall around her and holding her close, like all those nights before.

"Asseylum…" he whispered reverently.

He had never felt so whole.

(A/N)- AND THEN THEY STOPPED THE WAR AND GOT MARRIED AND NOTHING BAD EVER HAPPENED TO THEM AGAIN.

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