Even though Ulquiorra and Orihime have what I think are some of the most interesting interactions in Bleach, I've never tried to write them before. So, we'll see how it goes.

Also, the POV will switch between Orihime and Ulquiorra for each chapter, so some events may overlap.

It was a very dreary existence.

A vast gray desert shrouded in eternal night. Neverending. There was no shelter from enemies, no buildings, no civilization, nothing, just a wasteland of despair. The alternative was an underground forest full of hiding places for enemies, a dark pit of savagery.

Brute instinct: needed to avoid and, when necessary, defeat enemies. Brutality: needed to set an example to others. A warrior's tactics: needed to outwit the others and stand on top. All else was extraneous.

The weaker ones usually traveled in packs, to better protect themselves from the strong. But they were foolish trash who usually ended up eating one another anyway. There were only two beings other than yourself. There were enemies, who had the potential of damaging you. They had to be either subdued or killed. Then there was the trash, not worth troubling yourself over.

The only law was to eat or be eaten. The only thing worthy of respect was power greater than your own. There was nothing else to this gray, gray world.

Until, one day, there was a disturbance.

Someone entered Hueco Mundo. An outsider. But new souls were always entering Hueco Mundo, so he didn't think anything of it.

But then the trash started fleeing, as they did only in the face of extremely high spiritual pressures. This made him curious. Had another Vasto Lorde been created? It was a rare event, to be sure, but certainly not impossible.

Then the lower Menos started migrating as well, towards this new spiritual pressure. Like they were drawn to it.

Of course, he too could feel it too, somewhere out across the horizon.

Hollows continued migrating in that direction, and once they left they never returned. After a while, there were no other Hollows within even a close distance. That wouldn't do at all. Because although he was very powerful, he still needed nourishment.

He tried to put it off for as long as possible, but after a time his need for sustenance became dire, and he had no choice but to migrate as well. This new being had taken all of the Hollows within his territory, and would be punished for it.

He took to the air and advanced rapidly across the desert towards the spiritual pressure, just like so many lesser Hollows before him. It was coming from Las Noches, formerly another Vasto Lorde's territory.

There was someone far below in the desert sands, just standing there, gazing up at him. Someone without a mask. The source of the spiritual pressure. Strange. The only human souls he had seen in Hueco Mundo were weak and quickly devoured. Yet this one stood there completely unperturbed, with the most spiritual pressure he had ever encountered.

He did not understand.

…

The man was neither a Hollow nor a human. He was a shinigami, the age-old enemy of the Hollows. His name was Sosuke Aizen, and he ruled Las Noches now. Strange, that a shinigami should come to rule Hollows.

In Las Noches, there were perverse hybrid creatures, not quite Hollow and not quite shinigami. They called themselves Arrancars. Creatures who had been trash before now dared to be so presumptuous as to think that they could mock and berate him, on no account other than this. But by far the most arrogant among them were the ones who called themselves 'Espada'. One even thought to challenge him, and he killed them. He was even willing to devour this bizarre excuse for a Hollow, while the other Espada and Aizen looked on. He had won. He was the superior Hollow.

The concept of Arrancars was nevertheless intriguing to him, though. There was nothing else for him. He was as high as he could possibly go. He had not thought it possible to evolve further. But it would seem that he had been incorrect. He still had possibilities. He still had potential. He could progress. Maybe it really was possible to break the monotony of his current existence.

He decided to take Aizen's offer to be made into an Arrancar.

…

There were a few things Aizen told him ahead of time.

The first: "Don't fret. Let the Hogyoku do its work." Foolishness. As if he would fret about anything.

The second: "The Hogyoku can make you into whatever sort of Arrancar you want to be. However, if you want to gain an ability then you'll also have to give one up. Most choose to give up their defensive abilities in favor of offense." Pure idiocy. They might be able to defeat their opponents more quickly but if they took even a few hits then it was all over.

And the third was a warning: "It should be a painless process. However, if you become involuntary during the transformation then it will become excruciating. Once the Hogyoku's process is started, it cannot be stopped, regardless if the personal desires of the subject change."

And then it began.

Aizen vanished into darkness. Then the little Vasto Lorde realized that he could no longer move his body. He wondered if he'd been tricked somehow, but…no. Of course not. He was not easy to fool, and he certainly wouldn't get misled by a lowly shinigami.

So he thought about what sort of Arrancar he wanted to be. He was paralyzed in the dark, what else did he have to do, but think? He decided that he liked his abilities the way they were. He wouldn't have the sheer brute strength, but with the ability to regenerate, he'd undoubtedly last longer. Although, I wouldn't mind being a little taller. He was small, even for a Vasto Lorde.

He felt a tingling sensation all over-strange, but not necessarily unpleasant. He wondered if the Hogyoku could hear his thoughts. What a disturbing concept.

Then he felt something crumbling away from his face, and that was strangest of all, because when it was gone it felt like the air was clear and pure for the first time. Like he'd been breathing through a filter until now. The darkness lifted. Aizen was standing nearby. "What's your name, new comrade?"

"…Ulquiorra Cifer."

There were pieces of a shattered mask on the floor. He picked one up and looked at it. That had been on his face? And his fingers, they were so long and thin and pale now. He clenched and unclenched his fist. Well, it appeared to work, anyway.

He examined his body as soon as possible, standing in front of a mirror. He had never before seen his own appearance, so he wasn't entirely sure how different this new form was from his previous one. He only knew how it felt: strange and unfamiliar, like it didn't really fit him properly. He'd barely been able to stand on his new legs at first, much less to say walk a straight line. Sure, he'd had legs before, of course, but their usage had been optional. With this form? Not so much.

He looked like a human now, that was all there was to it, although he had retained his hole and part of his mask still clung stubbornly to his head. A Hollow that looked like a human. Strange, but in a way, the sort of creature that could be the perfect predator. Narrow shoulders, small hips, lean frame: he was still physically small, even as an Arrancar. And it didn't feel like he'd gotten any taller. Oh well.

One of the first things he got was clothing, which was really quite strange and something that Ulquiorra was unaccustomed to. He originally thought that the clothing served as some kind of armor, which is why Aizen wanted the Arrancars to wear it, but that was not the case. Clothing was easily torn and damaged, and it felt like it was constricting his movements. He just didn't see its practical value at first, truthfully. After a while, though, he came to understand. It was like its own unique form of protection.

There were many clothes to pick from, with many different sizes and designs. Ulquiorra preferred an outfit that would cover his hole. He wasn't sure why, but he felt a bit…hmm, what was the right term that could be applied? Self-conscious? Yes. He didn't want to flaunt his hole where everyone could always see it.

There were other things he learned about as well, as an Arrancar, that he had never really known about as a Hollow. Las Noches was a very strange place.

There was water - for personal hygiene as well as food and drink. At first he was confused as to its application for these purposes, but over time he figured out its proper usage.

There was light - artificial light, and dim, but light nonetheless. It was light enough to satisfy the purposes of Aizen and his two shinigami allies, but dark enough not to disturb creatures who were light-sensitive.

And most amazingly, there was sunlight. Ulquiorra had never known that it was possible for something so bright to exist in Hueco Mundo. He couldn't even go out into it at first. It hurt his eyes and temporarily blinded him, and so because of this he had despised this new innovation at first. It was something capable of hurting him and yet there was absolutely nothing he could do about it, leaving him with a sense of helplessness he was unaccustomed to and liked not at all. Gradually, though, he became acclimated to it, and over time he was able to stand under the sun without feeling bothered by it. It was after that point that he decided that sunlight wasn't so bad after all and was actually quite a remarkable thing.

It took more than basic resources to make a competent organization, though. Some rules and standards were necessary.

One was that there was no cannibalism. Arrancars were forbidden from devouring their own kind. Aizen's reasoning: That civilized creatures do not eat their own allies.

Another was that all Arrancars were required to keep up with their personal hygiene. Aizen himself was very meticulous about this and expected his subordinates to be the same way. Aizen's reasoning: That he was top dog and could make any sort of rules he damn well wanted.

Aizen was always to be obeyed. This was a given, anyway. He was powerful, he was cunning, he was clearly superior. Aizen's reasoning: That his ambitions would fail without absolute obedience.

Espadas were to administer Aizen's orders, or get Fraccions to do so in their stead. Arrancars were subordinate to more powerful Arrancars. Aizen's reasoning: That a clear chain of command was necessary to maintain order.

Arrancars were to always wear some form of clothing. Some of them were never able to get comfortable in clothing and wore the bare minimum necessary so that they wouldn't get in trouble. Aizen's reasoning: That unlike Hollows, Arrancars had distinctive anatomy, and civilized individuals did not necessarily expose all of it to everyone they came in contact with.

Fornication was never to take place in public areas. Once the Arrancars had figured out that there were things they could do with one another other than killing it had surprisingly become a problem. Aizen's reasoning: That there were some things it just wasn't fair to subject others to.

Killing allies was only somewhat tolerated. When you had a building full of ruthless and skilled killers, most of whom lacked any semblance of a moral compass, corpses inevitably turned up every once in a while. However, Aizen only tolerated a certain number of 'accidents' before he dealt out punishment. Aizen's reasoning: There were enough enemies out there to kill the Arrancars, without them killing each other.

There was one rule, however, that could absolutely, under no circumstances, ever be violated. No Arrancars were to leave Hueco Mundo without permission. Aizen had informed them all of his elaborate plan-to raise up an army of Hollows and create a key to enter the dimension of the Soul King, with the intention of coming to rule all realms, of both the living and the dead. However, the element of surprise was vital. It was important that the war be started on Aizen's terms. If the Soul Society was made aware before preparations were completed, then operations might be compromised.

To secure Hueco Mundo was impressive. But to atop to stand atop the world…that was above ambition. That was madness.

And yet if there was any being that could do it, then Sosuke Aizen was the one. He was a shinigami, the enemy of Hollows, yet he had brought Hollows to their knees before him. He had forced ordinarily solitary creatures to work together. He had brought order to a lawless place. He had made Hueco Mundo peaceful and united - well, as much as such a place could ever be, anyway. He was something beyond the level of a mere shinigami. Who else could accomplish so much alone but a being more akin to a god?

After Ulquiorra became an Arrancar, he had to amend his worldview somewhat. There was trash. There were enemies. There were allies. And there was Lord Aizen.

…

Because of his mask remnant, he learned to sleep almost exclusively on his right side. The mask wasn't heavy at all, just bulky. He didn't even really notice it was there except when it inconvenienced him. There were a few times his horn smacked into a wall or doorframe or something and knocked him off-balance.

Like the mask, the Hollow hole could never be gotten rid of, a physical reminder of a past that could never be completely discarded. Oddly, it was the most sensitive part of the body. It felt weird when anything even brushed against it, and touching the Hollow hole even a short period of time was a quick way to get someone excited. Ulquiorra had learned that little tidbit of information from Nnoitra Jiruga, even though it was something he hadn't particularly wanted to know.

Ulquiorra had been made an Espada by Lord Aizen not long after becoming an Arrancar. This meant, unfortunately, that he ended up interacting with the other Espada more often than he would have liked.

There was, of course, Nnoitra, a repugnant creature with an insatiable sex drive and sadomasochistic tendencies.

There was Szayel Aporro, a friend of Nnoitra's, an association that in of itself indicated how repulsive he was.

There was Grimmjow, an impulsive idiot whose bloodlust never seemed to subside.

Then there was the matter of Yammy.

Yammy and Ulquiorra made quite the odd couple. Yammy possessed great strength but not a great amount of intelligence or common sense. He was a brute force of destruction, levelling parts of Las Noches or killing minor Arrancars without a second thought. Lord Aizen had asked Ulquiorra to monitor Yammy, primarily because all of the other Espada were extremely impatient, didn't care enough to do the job correctly, or were insane. Or any mixture of the three. Most of the time, though, it didn't feel so much like 'monitoring' as it did 'babysitting'. To be fair, though, it wasn't just Yammy. Merely observing his fellow Espada in their day-to-day lives made him think it was really for the best that Arrancars couldn't reproduce.

Of course, he never actually voiced such things and just went through his life doing whatever he was supposed to be doing at any given time, following the rules, and not causing trouble. As a result of merely being himself, Ulquiorra was entrusted with a variety of tasks. Ulquiorra was honored that a powerful being like Lord Aizen had confidence in him, but even his deep well of patience sometimes ran dry. Being the dependable one was both a blessing and a curse, and so naturally he sometimes directed his annoyance at his undependable fellow Espada.

The main problem with many of his fellow Arrancar, that he could see, seemed to be that they didn't know what they wanted to be, more like Hollows or more like shinigami. They could go from civilized to brutish in an instant, like they were torn between their original Hollow nature and the new feelings and ways of thinking shinigami and humans had that the Arrancars had been incapable of fully experiencing as Hollows.

The most gratuitous example was the ongoing love-hate relationship between Nelliel and Nnoitra. It had started with Nnoitra hanging around the Tercera Espada a lot. For some reason, he paid particular attention to her over any other Arrancar. It became clear after a while that he had singled her out and was interested in claiming her as his mate - another strange thing. Hollows did not have mates or commitments to one another as other creatures did - a consequence of losing their hearts. And yet Nnoitra had developed a bond with Nelliel, an attachment to her that bordered on obsession. He dealt with it the only way he knew how - through violence and intimidation. In the same manner that the Espada could claim weaker Arrancars as Fraccions through the rule of dominance, so too did Nnoitra attempt to claim Nelliel. If he became strong enough to defeat her, then he could force her into submission and make her his. After all, when one Arrancar desired another, it was the game of dominance and submission that made the whole thing interesting.

It could have very well been the other way around, with Nelliel dominating Nnoitra. She could have done so at any time if she'd wanted to. But she didn't want to, and that was most of the problem. She was completely oblivious, but who could claim surprise at that? It wasn't like she had any experience with such things.

So then Nnoitra set his mind on forcing her to submit. It became almost a constant thing - Nnoitra challenging Nelliel and Nelliel beating him to a bloody pulp. Then Nnoitra would go to the medical ward, get his wounds healed, go find Nelliel, and try again. Rinse and repeat.

Eventually, though, Nnoitra's obsession with Nelliel degenerated from lust into pure violence, culminating in an incident that led to Nelliel's expulsion from the Espada. It was a shame, really. Lord Aizen had lost a perfectly good soldier, and for what?

Arrancars did not need to be bogged down by such things. They were a condensed mass of fighting ability and brute instinct - the perfect super soldier. All else was extraneous, nothing more than a weakness.

There was no love. There was no hate. Those concepts were mere illusion, conjured by those too weak to accept the harsh reality - the world cared for no one. It did not love or hate. It merely existed. A life was no more than a speck in the scheme of the universe, an insignificant thing that would eventually end. There was no point in forming attachments or taking time to cultivate pointless things, because they all would fall victim to time and fade away. There was only the present, the task at hand, doing the things necessary to prolong your existence another day.

Hollows and Arrancars were created and died. The ranks of the Espada changed. Only in Las Noches was there any indication of the passing of time. Outside, the same moon hung in the same sky over the same desert, eternally. There was a sense of balance and order to the world.

Well, until one day when Ulquiorra was sent out on a reconaissance mission with Yammy to the world of the living that is. What he saw there changed everything.

The "princess" will make her debut next chapter.