Giyuu dug his feet into the ground and sank lower into his stance, focusing on his breath. He had nothing left and he knew it, but he wasn't going to stop until either the sun rose or he was dead.

"Become a demon!" The demon's voice rang out again – all madness and corrupt sincerity – for what felt like the thousandth time that night. It had been hours, honestly, it felt like days, and he never stopped with his entreaties for Giyuu to become a demon. He conversed at length about the last Water Hashira he'd fought, a person whose name Giyuu knew well, as he still possessed the man's journal – it was old, the paper fragile to the point of being brittle. Not that Giyuu read it. He'd simply opened it once when he'd found it in a forgotten cupboard. He often found random things in the Water Estate that were left behind by former Water Hashira. Sensei had been an exception in their line that he survived. Giyuu found evidence of five previous Hashira who had not made it to retirement, and when he did he found it oddly comforting.

"We can fight together forever!" the demon sang.

Haven't we already been fighting forever?

The blood that ran down his arms was making the sword slippery in his hands, so he gripped it harder.

"What is your name?"

Giyuu did not respond. He barely talked to people who he liked so there was no way he was telling the demon who was killing him something like that. The demon circled him, and Giyuu knew that he was being toyed with. That he was outmatched had been clear to him from nearly the beginning, but he'd been allowed to survive for reasons that were still not entirely clear to him. After about an hour of battle, he had a theory that the demon enjoyed playing with it's food like a cat, but then later, it occurred to him that the damned thing was truly trying to coax him into becoming a demon and was dragging out the killing blow, waiting to see if he would change his mind.

If Giyuu was inclined to speak to the demon, which he was not, he would have told him to save his breath. Giyuu's human existence was fraught, and though he wasn't quite suicidal, he didn't like life nearly enough to have it extended preternaturally.

But still he fought, despite the steady flow of blood from wounds that drained his strength, the heaviness of his arms and legs, the pain he felt with each inhale – because if there was any chance at all that he could kill this demon, he would try.

It was his duty.

"I don't think you are doing very well, Water Hashira," the demon purred. "You have internal bleeding…I can smell it. I think it is your liver…that's not a good sign. You will be dead very soon. Please! Please become a demon with me!" he insisted.

Giyuu squeezed his eyes shut and took a deep breath, but still he did not respond.

The demon's voice became quieter, more serious, and he took a step closer, holding up a beckoning hand.

"You aren't going to make it…even if we stopped right now. You will die from your wounds. I think it would be best if you just came with me. We can have a long life together, fighting and becoming stronger!"

Giyuu's vision was beginning to narrow, things hazing out at the edges. He willed his fingers to hold his sword even though now they were numb and his arms shook with the effort to hold them up. He could no longer feel his legs.

One final move.

It was not giving up – it was simply the last thing he was capable of doing – and if he didn't do something soon he knew he'd drop his sword and his legs would go out and he'd die on his knees in front of the bastard, with his shattered eyes and psychotic smile and invitations to join him in hell.

Water Breathing…

He executed the fourth form, but he missed the demon's neck, instead burying his blade in its shoulder. As he moved past, the demon reached out and gripped the front of his haori, pulling him closer, his other hand coming up to grab a fistful of his hair in his hand.

This is it.

Giyuu did not close his eyes, he stared the demon down through everything, as his head was wrenched to the side, as he was drawn in.

As he felt sharp teeth bury themselves in his shoulder, he had a terrible feeling of regret, that he had not fought hard enough, that he was a disgrace, that he–

When he woke up, the demon who had been Tomioka Giyuu was possessed by a terrible, aching hunger. Another demon, who talked incessantly and who claimed to be his progenitor, led him through the woods toward a village where he assured him he could get something to eat. Giyuu was unable to focus on anything the other demon was saying. All he knew was the yawning emptiness that raged inside of him and he hoped that if he could just find something to eat, if he could just put something warm and gushing and alive into his mouth, maybe the howling in his abdomen would abate.

They came upon a house, and the other demon bid him to go inside and find something to eat. Giyuu complied, relieved, entering the home and finding a family of four – a man and woman and their two sons. He ate them with relish, pulling them apart with his hands, sucking the marrow out of their bones. He'd been born that night, but somehow he knew that he'd been empty for a long time, and so he filled himself with blood and meat until he was satisfied.

His companion wanted to fight afterwards, and Giyuu was easy to persuade, as the demon was getting on his nerves. He was taken apart, limb from limb many times that night – his back broken, heart ripped out, fingers snapped, his head torn from his shoulders. But soon after, every time, he became whole, and was then pressed into battle yet again.

This went on for many nights, and his companion often asked him about his name, but to his knowledge he did not have one. This annoyed the other demon quite a bit.

"Why couldn't you have just told me your name before?"

Giyuu had no idea what before the demon was talking about, so he ignored him.

"Why don't you speak? Do you not have a tongue?" the demon exclaimed, and he reached into Giyuu's mouth and ripped out his tongue.

When it had grown back Giyuu gave him an irritated scowl. "Ouch," he said quietly.

"Finally!" the other demon growled. "I was beginning to think there was something wrong with your head."

Giyuu tipped his head to the side, trying to imagine what that might mean, but then the other demon leapt into the air and brought his foot down on his head, crushing it in one blow.

This went on for months. Over time, Giyuu learned to fight with his hands against the demon whose name was Akaza. Akaza was often agitated that he did not know his name and also that he wasn't as good of a fighter as he'd been before (whatever that meant). There was sometimes talk of finding him a sword, that perhaps he'd be better if he had a weapon he knew how to wield, but Giyuu had no memory of knowing how to fight with one, so Akaza taught him to fight with his fists and feet. Akaza enjoyed teaching him these things and then breaking his arms and legs in dozens of ways in order to teach him how to become stronger. Giyuu tried, but his hunger was vast – an absolute beast of a thing inside himself that he could barely contain – and so he had to eat much more than Akaza in order to even be able to fight, let alone regenerate, after being torn apart so many times.

"You are getting better…but you are still not like you were," Akaza said disdainfully.

Giyuu could only stand there and take this criticism silently, because he had absolutely no idea what the other demon was talking about.

He did, however, become aware of a few things early on.

First, he felt something of an affinity for Akaza. It was strange, because he hated him, in fact he truly reviled him, but on the few occasions since he'd awoken that Akaza had been called away, Giyuu found himself a little lost when he was gone. It was just barely an emotion (as a human he'd excelled at repressing his emotions to avoid certain truths, and as a demon he unknowingly took this to a new level)…so it was not that he missed him, exactly (maybe?). It was a physical sensation of being unmoored in some indefinable way. It was not as though he didn't know how to hunt on his own, and the gods knew he didn't mind having a break from being torn to bits six times a night, but still he felt adrift without him.

Another thing he was aware of was that there was a tether in his mind to someone else, and that someone was also able to look out of his own eyes. He sometimes sensed that they were rifling through his thoughts as if looking for something. When he asked Akaza about it, the other demon went silent.

"That is our Master. We don't speak of him. Put him out of your mind and focus on getting stronger. I want us to fight like we did on the last night of your life."

"What night was that, Akaza?"

Akaza merely looked at him in irritation and shook his head.

"I liked you better as a Demon Slayer."

Giyuu hid the shudder that went through him but he did not ask what a Demon Slayer was.

Another thing he knew in the core of his being (in what had once been his soul) was that if he understood the dynamics of a family he was hunting, he had a strong aversion to killing the oldest female child in the family. It was an odd quirk that Akaza brushed off. "It happens," he'd said nonchalantly one night when Giyuu asked him about it as they crouched on a rooftop overlooking a town so large that Giyuu suspected it might be part of a city.

"I can't eat women," Akaza said with something like hesitation in his voice. "I mean I can kill them…I just choose not to. I find it…distasteful. And to eat one?" Akaza made a face and shook his head.

"Why?" Giyuu asked as he looked at Akaza and thought that the idea was preposterous, but then he imagined it was not nearly so ridiculous as his particular dislike for eating older sisters, so when Akaza merely shrugged and didn't respond he didn't ask any further questions.

One night they happened upon a group of Demon Slayers, and Giyuu came to know that there was a group of organized humans who trained to fight and kill demons. They used special swords that were capable of truly killing them. Giyuu was skeptical that being beheaded by weak humans was enough to kill him, as Akaza made a habit of ripping his head from his shoulders at least once a month.

"Believe it…or not. Your choice," Akaza quipped lightly as they watched the Slayers milling about on the ground far below where they hid in the trees.

When they finally jumped down, Giyuu approached a pair of slayers and one of them turned white and asked in a tremulous voice – "Tomioka-sama?" Giyuu paused, not because he recognized the name, but rather he was distracted by the fact that he didn't know if the girl before him was an older sister or not.

"Ha!" Akaza crowed. "Finally! A name!"

They killed the entire squad of weak humans, and Giyuu wondered why they bothered calling themselves Demon Slayers at all.

Giyuu was nowhere near as strong as Akaza, and would not be so for decades (if he survived that long) but there was something of the Water Hashira that he'd once been that remained in his fighting spirit, though he was unaware of it. He had only just begun to develop a Blood Art that was unique to him and he used water in its wielding.

He also grew into his demon form, and it seemed water played its part in that as well. When he was first transformed he was nothing but a dirtied, bloodied human-looking thing for a while. He discarded his sword and ridiculous haori immediately. Over time, as his body became stronger, as his shoulders grew broader and his hands lengthened into claws, he tore away the top of his uniform, though he kept the bottom half intact. He flat out refused to go barefoot despite Akaza's repeated promises that it was much more comfortable than zori sandals. His fangs lengthened, and the glacial depths of his eyes grew wide and unnatural. And then one night they appeared on his flesh – hazy at first – a blue and white sweeping wave pattern of water. It began on his back and extended across his shoulder blades like wings, cresting up over his shoulders and onto his chest.

(And Akaza was reminded of his former life as the Water Hashira. He toyed with telling him, but chose not to. He tried to keep secrets from Giyuu as a way of keeping him around, but he knew in his cold demon heart that he would soon either have to kill him or let him go out into the world on his own. He was oddly on the fence about the matter.)

"Hey Tomioka!" he called out as he flew through the air, aiming a kick that would have surely cut Giyuu in half if he hadn't sidestepped at the last possible second to get out of the way.

"Not now Akaza," Giyuu said indifferently in a manner that Akaza was truly starting to find grating. "I want to get to the village before dawn. I'm hungry."

"I'm hungry, I'm hungry," Akaza mimicked in a derisive tone. "You are always hungry and no fun at all."

"Just leave me alone," Giyuu sighed.

(Akaza stared at him as he walked toward the village, thinking he might do that very thing, and soon. Whether or not he would do it leaving Giyuu in pieces nailed to a tree to face the dawn remained to be seen.)

One final thing that Giyuu was aware of was that there was something rather special in the world that Akaza was looking for. It flashed in his mind only once when he first became conscious, and though he didn't think about it directly for a long time, it left an afterimage in his mind like fire in his eyes if he stared at it for too long. It wasn't something that he spoke about, as he did not understand the significance of the information. He had a vague feeling that it was something important to their mysterious master, but whenever that thought began to creep into his head, he pushed it away quickly. He knew that Akaza was sometimes summoned by their master, and afterwards, when he returned, he was usually injured and sullen and uncharacteristically quiet. Giyuu didn't want to be summoned anywhere, so he kept his mind blank and quiet, a state that seemed to come quite naturally to him. Unless he was hungry – and then his mind was nothing but rage and ache for the taste of blood and meat.

Giyuu traveled away from Akaza for a few nights, something that had been happening with more and more frequency. The gnawing affinity was always there but he found he could bear being away for a longer period of time, even though it clung to the barest edges of his mind. But the hunger, the raw clenching emptiness that seemed to rip through the core of his being was always more pressing, so he followed that instead of his progenitor when it suited him. He knew Akaza needed to eat far less than he did, and part of him wished that it was true for him as well, but then when he was eating, rending flesh from bone and lapping up the blood from the floor or the walls, he didn't want for it to ever end.

At one point in his solitary travels, he found himself in a cave, staring out into a dark, overcast afternoon storm. The wind whipped through the trees, and the rain fell in heavy sheets. He watched the storm rage, the lightning cutting through the darkened sky. The thunder cracked, reverberating through the forest, the sound bouncing off the walls of the cave as he peered out.

Something like a spell fell over him. He felt a calm like he'd never felt as a demon (or a human for that matter), not quite like a dead calm –

(what?)

– but for once he wasn't hungry, nor was he looking over his shoulder waiting for Akaza's next attack. He looked up at the sky, watching the thickening and the thinning of the clouds as they shifted. It was odd because it was something that he never did – stop to look at the natural world, his existence had narrowed to nothing but blood and death and eating – but for some reason he paused, and it summoned an urgent feeling that he was forgetting something important. He looked down at the forest floor, shaking his head to clear it, and at that moment lightning flashed and he noticed something odd. It was star-shaped, edged with iridescence down its delicate folds, and Giyuu recognized that it was something with petals. It was a flower…a lily…a spider lily. And it was blue.

The tether was tugged lightly, as though a spider had stepped onto a strand of its web, sensing for vibrations. Giyuu stepped quickly toward the flower and bent down to pluck it, just as the tether snapped tight. The ominous sound of a stringed instrument sang with power and a wall of light opened before him. Without warning he was drawn into it.

Later, Giyuu would wonder what possessed him. He took the flower and crushed it in his hand before stuffing it into his mouth and swallowing it whole.