Author's Note: Played Three Houses, loved it, and needed more in my life. The evolving relationship between Edelgard and Byleth was something wonderful to behold, and I knew I had to do some writing for it. I'm not ready to say goodbye to this pair yet.

As for the tone of this story, if you've read my previous Fire Emblem work, Cerulean Heart, that will give you an idea. It'll be a long form, narrative focused piece with a mix of novelised versions of battles from various chapters, adapted scenes from the story and plenty of original scenes, too. Here and there I also intend to do the odd chapter focusing back on their Monastery days, usually to tie into something in the current arc. The growing romance between the pair will be a heavy feature, but it won't descend into pure fluff (maybe a few scenes here and there)

Hope you enjoy, this first chapter is pretty meaty, don't know if they'll all be this long, I never really plan these things out.

He felt adrift in a tempest of nothingness. He knew it was silent, yet he could hear voices. He knew he had no solid form, yet he felt the grab and pull of raging winds around him. Without knowing how, he understood that he had been here for an age, yet no time had passed.

"Professor! It's good to see you." A voice called out. He couldn't place it.

"Ah, Professor, I was wondering if you could help me with this project…" Another voice called from the nothing around him.

"Professor…"

"Professor!"

"Good morning, Professor!"

"My teacher…"

They called out endlessly. Deep voices, soft voices, tired voices, happy voices. Voices from before he was here. As the voices picked up intensity, the endless black around him began to muddle. Like a perfectly still lake hit by a pebble, the expanse began to ripple and fracture. Mixing into the darkness like swirling ink came colours, a softer black, red, purples, blues, greens, beginning to form constantly shifting shapes, shapes that he recognised.

A young girl with messy, purple hair, smiling up at him timidly.

A smiling, handsome young man with striking orange eyes bowing to him.

A woman with tanned skin and a mark beneath her right eye, swinging a sword at a practice dummy.

A beautiful woman with long, flowing hair topped with a hat, waving happily to him from across a field of grass.

A green haired boy, dozing off in a library with a book used as a pillow.

A short lad with striking blue hair, gesturing enthusiastically at a weapon rack.

A man with pale skin and eyes like a snake, giving him a curt, cutting smile.

The images mixed together and apart, forming scenes that made sense together and alone, equal parts a portrait and a puzzle.

"Ah, Professor, is the lesson over already?" Came a tired voice.

"Professor! You gotta teach me that technique!"

"I would like to be learning more from you, Professor."

Eventually, one voice began to win out amongst them all. A soft voice, yet there was clear authority in it, just as there was clear affection.

"My teacher…"

The swirling images around him began to break down and convalesce into a new shape.

"I've never told anyone about my past before…"

The new shape encompassed his entire vision, it was all he could see now, all he could hear. The colours were starting to settle into their new form. Long, flowing silver hair. Pale skin, a woman's face.

"They violated our bodies by cutting open our very flesh…"

The shape was beginning to settle. Like all the shapes before it, it was so very familiar, and stirred so many feelings in him… But yet… This one was different

"Sometimes I wish I could spend just one whole day doing nothing and gorging myself on sweets!"

To his surprise, a voice replied.

"Let's do just that."

Though the shape before him had still not fully formed, he could see, clear as day, a beaming smile on her face.

"Do you mean it?"

The shape before him changed and changed again, but it was always of this woman. Her face, pained, standing beneath a sea of stars. A look of determination as they stood on an open field. Her cheeks, burning red, glancing aside. More and more of these images appeared until finally, it settled on one.

Throughout it all, he realised, the shape and colour of her eyes had remained muddled and hidden from him. But now… He stared into them. A pale lavender, the eyes were wide in disbelief. Instead of the clothes he had seen her wear in all the previous memories, she now wore armour that looked far too big for her. A black and red cloak adorned the plate, with red feathers placed on the shoulder pads. All around them was an ancient tomb, littered with bodies and stained in blood.

"My teacher...I… Thank you."

The woman reached out her hand, and he reached for it back.

"Edelgard..."

Byleth gasped as his head broke the water. It felt like the first breath he had taken in years. So long had he been in darkness, that even the light from the grey, clouded sky above stung his eyes.

He thrashed his arms madly, gasping for air once again before the current took him under. It was only a few seconds until he managed to push himself up again, looking around in a manic fashion. Despite the water in his eyes and the sting of the sun, he managed to make out the river bank, not far away. Relying on pure instinct, he began to coordinate his movements enough to swim. It was rough, inelegant, and exhausting, his body felt stiff and with each swing of an arm, more water splashed into his mouth, his eyes, his nose.

After a tremendous effort, Byleth swung his arm forward once more, and found resistance that wasn't just water. His fingers hit the muddy banking, gouging into the ground. He pulled himself forward on this purchase, then repeated the motion with his other arm, again and again until he'd dragged himself out of the water. When his knees were able to find resistance against the ground too, Byleth began to crawl forward, still gasping for breaths. He climbed slowly up the river's banking, until he got to the flat earth above, then turned over onto his back, collapsing.

"Wh… Where…?" Byleth asked aloud. His eyes had adjusted now, and after a few more minutes of catching his breath, he rolled over, pushing himself to his feet, finally taking in his surroundings, though he quickly realised it was no where he recognised. There was the entrance to a large woodland on the opposite side of the river, and not too far behind him he could make out some houses.

"A village…" He muttered, wincing slightly in pain. His throat felt raw and dry, as if he hadn't used it in years. He began to walk toward the village, before something on the river's edge caught his eye. It was snagged between a pair of rocks, only a short distance down from where he'd dragged himself out. It was a sword that looked as if it had been crafted from bone, with a cross guard like a bat's wings. One look at the Sword of the Creator brought it all crashing back.

The siege of Garreg Mach, the battle against the Knights of Seiros and Rhe- No… The Immaculate One. Edelgard had declared war against the Church, and he had joined her. The siege was bloody, but they had been winning. He and Edelgard had fought Rhea, beaten her…

He winced, gripping his head.

What happened…? Why am I here?

The image of Rhea taking her monstrous form filled his mind. He raised his blade, ready to fight, and remembers Edelgard screaming his name… Then nothing.

Edelgard.

The war… There was a war. What had happened to him? To Edelgard? To the other students? Panic and adrenaline surged through his body, replacing the fatigue in an instant. He skidded down the banking, grabbing the Relic, and quickly took off for the village.

Five years… How could it have been five years? Byleth thought to himself. As he entered the village, he got no small amount of strange, fearful glances. One particularly brave villager approached him, sword drawn, until Byleth assured him he meant no harm. After that, he'd quizzed the man. Thinking back, he must've looked stark raving mad, not that he cared that much.

Five years since Emperor Edelgard had declared her war on the Church and, as an extent, the Kingdom and the Alliance. For five years he'd been… Wherever he had been. Asleep? Dead? The villager had told him that the Imperial Army had taken us base in the Monastery and, quite recently, the Emperor and her personal entourage had returned too. That was all he needed to hear before he bolted off, ignoring the shouted warnings.

They're waiting for me… My students… My friends…

Despite how sore his body felt, Byleth sprinted through the woods, towards where the villager had pointed. Garreg Mach is just a short walk through the trees and up the hill He had said. It wasn't short enough. He had to get there now. He had to get back to them. They needed him.

And I need them. He thought to himself. He hadn't even given a thought as to how he'd get in. If the Monastery was under the control of the Imperial army, there would certainly be checkpoints, guards and the like. He could think it through when he got there, for now, he had to push on. He burst through the trees, emerging from the woods, and looked up before him. Garreg Mach… He kept going.

Edelgard stared out the window, eyes focused on a pair of birds idling on the monastery walls. She knew Hubert was talking to her, recounting a report he had received from Imperial spies in Alliance territory. It wasn't the most important report, honestly, it wasn't even worth her time, but she knew she should be listening regardless. But it was impossible. It was that time of year again and her thoughts wouldn't be on anything else for the next few nights.

"Your Majesty…" Hubert called. "Your Majesty, please, though this report will hardly affect the war effort, you need to be kept informed." Edelgard glanced back at him, finally pulled from her reverie.

"I… Forgive me, Hubert. Please, carry on." Hubert nodded, then finished his report.

"Is that all?" Edelgard asked. Hubert nodded.

"Yes, Your Majesty." He said, bowing deeply.

"Then you may leave me, Hubert. Get some rest and something to eat. Even you have limits." Edelgard said, offering him a small smile. Hubert nodded, turned to leave, then paused.

"Your Majesty… I know it is that time of year, but-" Hubert began. Edelgard glanced aside.

"Please, Hubert. I don't need it… Not right now. Not today." Edelgard said. Hubert hesitated, opening his mouth for a moment. Deciding not to speak, he simply bowed again and left. Edelgard's gaze turned back to the window, back to the walls. One of the birds from before had flown away, she realised, leaving the other squatting alone. She sighed, getting out of her chair. She needed to be alone. Somewhere they wouldn't find her. Suddenly, a memory from years past came back to her.

"Let's all agree to meet back here in five years time."

She smiled bitterly… What had she been thinking, making a promise like that, knowing what she was going to do so soon after? She shook her head, trying to physically dislodge the memory, but it stuck to her.

"Five years…" She mused, when suddenly a thought struck her. A place where no one would go looking for her, a place of solitude. There was really only one such place in the Monastery that fit that description. Pulling on her large cloak and fitting her crown upon her head, she left her office and made for the Goddess Tower.

Byleth hurried through the Monastery's lower paths, a cloak pulled tightly over his head to hide his hair. As he approached the first checkpoint, by some divine fortune, the guards standing watch had been former Black Eagle students turned imperial soldiers. They had recognised him immediately. Between his hair and the sword he was unmistakable, after all, and the pair were quick to inform him that Edelgard was indeed in the Monastery, offering to escort him to her personally.

"Her Majesty will be overjoyed!" Exclaimed Karl, one of the two guards, a huge grin on his face.

"With the Professor back, we might change the tide of this war." He continued. Byleth smiled warmly at them.

So they're not winning… But it doesn't seem like they're losing he thought to himself. After declining their offer for an escort, Byleth took a written permission slip from the pair in case he was stopped again, and also requested a hood to hide his identity.

"I want to make it to E- Her Majesty without interruption" He had told them, and the former students were happy to comply. He had now left the markets and entered the central grounds of the Monastery, his eyes darting around for any sign of those he knew. He had hoped to go unrecognised by his former core group of students until he reconnected with Edelgard but…. After five years of war, would all of them even be alive? Would any of them? He shook his head and pressed on, simply letting his feet guide him, no solid plan in place.

As he crossed the green outside the former classrooms of the three houses, he couldn't help but note how different the Monastery felt. Where there had once been flags adorned with the church's symbol, now flew the banners of the Empire. Spots that had once been filled with groups of chattering students now had crates stacked high, or soldiers milling around, busying themselves with whatever work they were given. He kept going, pushing into the dining hall. It was much the same here. Though there was still an obvious din of voices in the air, it was… different. Less laughter, he noted. In place of students, yet again, were more soldiers, the food on their plates a far-cry from the high-quality dishes served by the former cooks.

He kept going, lost in thought, until finally he made it to the large bridge before the chapel. He looked up at it structure, noting the damage from the siege all those years ago had yet to be repaired. It wasn't surprising, of course, nor did he ever particularly care for faith of Seiros itself but… For some reason he felt a pang in his chest. His eyes then drifted from the chapel to the structure next to it. Taller than the chapel, covered in ivy, the tower looked none the worse for wear as a result of the war.

"The Goddess Tower…" He whispered, a memory coming to him unbidden.

"Let's all promise to meet back here five years from today." Came her voice.

Five years Byleth thought.

It couldn't have been five years to the day, could it…? I didn't ask the date…

Byleth pulled his lips back, exhaling through his teeth. It was a stupid, hopeful thought. Honestly, he should've checked Rhea's former office first, it was the most obvious place for Edelgard to set herself up… But still… Something compelled him.

She's in there… She's waiting…

He pushed forward once more, heading toward the tower.

Byleth slowly climbed the stairs, a scant amount of sunlight breaking through the thick mat of leaves and ivy that covered the windows. The entrance had been unguarded, and the tower door left unlocked. Even now it felt like a foolish waste of time, hoping for her to be here, waiting for him. Yet with each stair he climbed, he felt his anticipation rising. The final few steps that led to the top chamber were in sight. He paused for just a moment, took a deep breath and walked forward, coming around the corner to see…

Her.

She was facing away from him. Her hair was different, her clothes were different… Even the way she stood was different. But it was unmistakably her. He began to walk forward, opening his mouth to make his presence known, before the sound of his footsteps alerted her.

"Halt! Who's there?!" She cried, turning around quickly, hand going to the sword on her waist. Byleth took another step forward. Edelgard froze, staring at him in shock. Her mouth hung open for a moment, her words clearly caught in her throat. Byleth took another step.

"It's me." He said simply. Her eyes went wide as her lower lip began to quiver.

"It can't be… Professor?" She asked. She stepped forward, reaching a hand out as if she meant to touch him, to make sure he wasn't some illusion.

"Is it really you…? But… I searched everywhere and never found a trace!" She said, almost as if she was arguing with herself, that he couldn't possibly be here. Byleth stared at her, his eyes meeting her own. There was so much he wanted to say, to ask but… Words had never been his strong suit. What could he possibly say to her right now? What could make up for five years of his absence?

"My Teacher… What have you been doing all this time?!" She asked, her tone almost accusatory.

"Where have you been?!" She asked again. She looked pained, already he could see the sting of tears in her eyes.

"I…" Byleth began. "I was sleeping." He likely could have given a more in-depth answer than that, but… Even he didn't understand it himself yet. Edelgard looked at him, her face a mixture of shock, offence, disbelief, that he'd give such a flippant answer. Then, before he knew it, her cheeks began to tinge red. A small smile came to her face as the tears started to trickle down her cheeks. When she spoke, she somehow managed to sound like she was shocked at his dismissive answer, and holding back a laugh.

"Joking?! At a time like this?!" She closed the gap between them, her hands coming up to grab his arms. The smile on her face slowly faded, but the light stayed in her eyes.

"You do realise it's been more than five years since you disappeared! Do you have any idea how guilty I felt? How broken my heart was!" Edelgard said, the words pouring forth now. Words she'd clearly waited so long to say.

"I searched high and low after you vanished! Although there was no proof I somehow knew you were still alive!" She gripped his arms tighter, her voice beginning to waver.

"All this time, I've led everyone as best I could, and fought with all my heart. It's been a difficult path to walk alone…" She said, taking a deep breath afterwards. She met his eyes, tears still stinging her own. He didn't know what to say. What could he say in response to that? He knew that amongst all people that she knew, he was the only one she'd let in. The only one she could ever let her guard down around, and when she finally took the first step towards her destiny, down her path stained with blood, he knew that the thought of him being by her side had alleviated some of the tremendous burden she would have to bare. That, come what may, she wouldn't be alone.

And right when it all began, he vanished.

"Edelgard… I…" Byleth began. She looked at him expectantly.

"I'm here now." Was all he could manage. Edelgard's bottom lip quivered slightly. She let go of his arms, then slipped her own around him. She pulled him against her, her arms grasping him so tightly it was as if she was afraid he'd disappear the moment she let go. Byleth didn't return the hug, even as she gently rested her head against his cheek.

"Welcome back, my teacher. I'm so happy you're safe." Byleth relaxed slightly into the embrace, resting his head against hers in turn. This was new territory to him. He had no idea how to react, or even what an appropriate response would be here. As she pulled him tighter, her body pressing against his, Byleth could feel an odd sensation against his chest. Beating, rhythmic.

Her heart he realised. It was beating wildly, so loud he could feel it against him.

"Edelgard." Byleth said. She didn't break the grasp, or make a sound, but he knew she was waiting for him to continue.

"I'm sorry." She didn't reply, but he felt her grasp him tighter.

I won't leave you alone again. He thought to himself.

Not you, or any of the others. I swear. Byleth stayed stationary, letting her hold him for as long as was needed. In this moment, he wouldn't dare to deny her anything.

The sun had set long ago, and now the moon sat high in the sky. The clouds from the morning had long vanished, and the full moon provided more than enough light for him to get around by. Byleth walked alone as he made his way through the Monastery grounds, mind still swimming with information. He had tried to sleep on the matter, but it was no use. He felt restless and needed the cold night air.

Five years. Five years of non-stop warfare. And, by Edelgard's report, neither side had much to show for it. They'd been locked in a stalemate, Claude managing to keep the Alliance in a state of tentative neutrality, whilst Rhea had fled to the Kingdom, seeking shelter from Dimitri. Since then, skirmishes and conflicts were common, with towns and fortresses being sieged, captured, then re-captured in turn. Any decisive victory was often met with a defeat in another location, the war grinding its participants down on all fronts. Edelgard, however, had a plan to change that, and with his arrival, she was confident she could do it. A decisive strike against the Alliance, first to take a key location, a large, fortifiable bridge over a river that cut through Alliance territory, then onto the Alliance capital. She hoped by striking at and defeating Claude, the pro-Adrestian forces within the Alliance would openly flock to her side, allowing her to peacefully take control over the Alliance lands. It was a bold, decisive strategy. He had hardly understood the political climate of Fódlan before the war, so any input he had on the matter now would likely be even more useless. But he trusted Edelgard, and that was enough for him. All he had to do was lead her armies to victory. To show up, to fight, to win. Was it really any different than when he was a mercenary?

The amount of lives you would be held responsible for, for one… He thought, sighing to himself.

But it was not just the thought of the war that kept him restless. The reunion with his former students has been quite a shock, too. He recognised all of them in an instant, but they had all changed so much. They'd grown taller, their hair had changed, their clothes had changed. Even their voices had changed, albeit subtly. But the biggest change had been their eyes. They all looked so tired… Well, except Caspar, Byleth thought to himself, a small smile forming on his lips.

The war had clearly taken its toll. Dorothea's beaming smile had become far more subdued. Ferdinand's glowing demeanour, far more serious. The rest, too, had changed in so many small ways, but… The smile on their faces when they saw him. The sense of hope he felt in the room as they talked of how his return will be the turning point of the war. The smile that had crept onto his face grew wider style. They had missed him dearly. Just as he had missed them. He wanted to tell them that for as long as he was sleeping, he dreamt of them, of his time with them. How those cherished memories had stayed with him even to another plane of being. But he didn't, of course. The words came easy in his mind but, speaking them out loud was another matter entirely.

Byleth slowed his pace as he arrived to his destination. The cemetery. Just as he hadn't seen his students for five years, neither had he come to see his father. The bright moonlight cast an eerie glow on the graves of the fallen, and the chill night wind that blew in, rustling the grass and the leaves in the trees, only added to the effect.

Should've brought flowers he thought to himself as he walked down the stairs. He approached the grave of his parents, his father having been buried alongside his late mother, and knelt down. To his surprise, the grave had fresh flowers on it, and had clearly been taken well care of. He was half expecting to see it had degraded from neglect, but…

He reached out a hand, touching the headstone. There was so much he'd wanted to say to the man. So much he'd never get to say, now. Their relationship had been a distant one, as far as he could remember, though he couldn't blame that on his father. He had walked through life like a dead man. Never really feeling, never really talking. Hell, barely even thinking that much. He just did as he was told, never questioning the orders, never thinking about the lives he took. Until he came here, until he met the students and finally, for the first time in his life, had people that relied on him.

By the time his father was taken from him, he was feeling his emotions more keenly than ever. For the first time, he felt a genuine connection between he and his father. When he saw the smile on his father's face, so happy and proud of his son for finally finding a place to belong… It had made him happy beyond words.

So many things left unsaid…

"And I'm no different… Even now…" Byleth sighed. He couldn't bring himself to tell the students how much he missed them. Couldn't bring himself to tell Edelgard that, amongst all that he dreamed of, it was of her, first and foremost, that held the largest place in his memories.

"Professor?"

Byleth jumped to his feet, whirling around in an instant, to see the shocked face of Edelgard. She was wearing a long, red gown, covering her body from neck to toe. Her hair, which had been up in intricate buns, now flowed freely, the same as he remembered it being from five years ago. They stared in silence for a moment, before a soft smile crept on her lips.

"Twice in a day we've happened upon each other now. Though at least I got to startle you, this time." Edelgard said. Byleth let out his held breath and smile softly.

"I'm sorry. I wasn't expecting anyone to come here at this hour." Byleth said.

"Nor I," Edelgard began. "Which begs the question as to what you-..." Edelgard stopped, looking at the gravestone behind Byleth.

"I'm sorry. That was a silly thing to ask." She finished. Byleth shook his head.

"No, it's fine. Sleep proved too elusive, so I came to see the grave. I was honestly expecting it to be neglected…" Byleth said, trailing off. Edelgard glanced aside, looking a little embarrassed.

"Ah, well, I made sure that no such thing would happen. I knew that, when you'd come back to us, it would do your heart well to see it well looked after." Edelgard said. Byleth smiled at her, feeling genuinely touched.

"Thank you, Edelgard. It means more than you know." He paused for a moment, before continuing. "And you? What brings you here?" He asked. Edelgard closed her eyes and sighed, a sudden strong gust of wind hitting the pair causing her hair to billow beside her.

"I know it's been a long time, but do you remember the talk we had one night, long ago? When you came into my room?" Edelgard said. Though five years had passed, Byleth's memory of his time at the Monastery was as clear as it had even been. For him, it was as if only a few months, not years, had passed since that night.

"Nightmares," Byleth said. "I'm sorry." Edelgard gave him a dismissive smile.

"I had thought I would be free of them tonight. This day has brought more joy and peace to my mind than any in recent memory," Edelgard sighed. "But it was no use. Seems my burdens are not that easily lifted." Edelgard said, walking forward, further into the cemetery, where many more graves stretched out.

"When I can't sleep, I come here. It's almost peaceful, in a way, when sleep evades you, to go visit those who will now sleep forever." Edelgard said.

"And it's a reminder, too. Each grave makes me think of how many I've sent to their own, these last five years. Five long years of war and death… All because of me." Edelgard gave a bitter smile.

"Though we walk the right path, it doesn't change anything. One such as I am undeserving of a sleep not haunted by spectres."

Byleth stared at her in silence. They'd often meet up at night after she confided in him. She had told him she couldn't bare to stay inside when the nightmares came, so she'd walk the grounds at night until exhaustion overcame her. That had changed, though, in the last few months before his disappearance. Byleth himself was a night owl and had never needed much sleep, besides. It took some convincing, but whenever a particularly terrible nightmare had haunted her, she would quietly sneak to his room, knock on the door, and the pair would walk the grounds together. Simply talking. About the nightmare, her past, lesson subjects… Anything to take her mind off it.

But she hadn't had that for such a long time. She'd been forced to bare it alone, right when she needed him most.

So many things left unsaid… I can't let it happen again.

Byleth crossed the distance between them, pulling Edelgard into a tight embrace. Edelgard let out a small gasp, this clearly being the last thing she was expecting.

"M-my teacher!" She gasped. Byleth snaked one arm around her lower back, the other running through her hair to be placed on the back of her head.

"I'm sorry." He began. "Five long years of war… Five years where you needed me, more than ever. Five years worth of nightmares I wasn't there for." Byleth said.

"My Teacher..." Edelgard said, her voice shaking a little. Her arms now pulled around him, returning the embrace.

"For everyone that has been a victim of the Church. For everyone that has been a victim of Crests. And for those we can still save. I'll be by your side, Edelgard, until the very end." Byleth said. Edelgard leaned back a little, smiling up at him tenderly.

"And that is how I know we won't fail. Thank you, from the bottom of my heart." Edelgard leaned her head back against him. Once again, he could feel her heart beating. Though he knew his own would never beat like hers, it didn't change what he felt in it. The embers that had kindled during his time teaching his students was becoming a blaze. What it meant, and why it burned so brightly for the woman in front of him, he still couldn't fully say. But he'd find the answers by her side.

That, he was certain of.