Hello, readers! (I just realized I should have put this note at the beginning, so I'm going to do that, too, so if you've just started reading this story you will have already seen it and can skip it.)

Before we get started, I just want to explain a few things real quick. First, this story is complete up to chapter 11, so I will be posting a new chapter every couple of days until I get there, and then I'll be moving to updates every other week. It's currently plotted out for 16 chapters though I can't say it won't grow in the process. If you can't wait and want to catch up, you can find me at A03 under the same name.

Second, I want to thank you for reading! It makes me very happy to know people are enjoying my story. If you want to make me extra happy, I really love getting reviews~! Constructive criticism is especially welcome, but also even if you just want to say "I like this story," please, let me know!

Third, a question. I notice that the terms of service say FFN doesn't accept explicit content and it's grounds for banning? I've been an A03 person for a while so I'm not sure how serious they are about that. I have a few smutty one-shots that I could put up here but I don't want to get in trouble, so any longtime users could tell me about this, I would appreciate it. Also this story will eventually contain a lot (i.e. several entire chapters, two of which are much longer than standard chapters because I'm all about that detail) of extremely explicit sex, though I could edit some of it out if I have to, or tone it down, but I really don't want to do that.

Fourth, this story contains NO MPREG. I realized that it might look like it's shaping up to be that kind of story, but I assure you, it's something a little different than a standard A/B/O or heat concept.

Lastly, this chapter might be a little confusing, especially as it will contain some Spanish words that go untranslated. Don't worry, answers are forthcoming : )

And now, the man you've all been waiting for…

"Where's Ichigo Kurosaki?" Grimmjow asked, feeling damn suspicious about his disappearance. "I ain't seen him for three days."

"Aboard ship. He is indisposed," Kuchiki replied, giving nothing away as he looked up at Grimmjow from the chair behind his desk

"The fuck is that supposed to mean?" Grimmjow spat, starting to get annoyed. He'd seen Ichigo nearly every day since the Shinigami showed up, at least for a minute or two here and there. Then, three days ago, Ichigo had dropped off the face of the world and no one had seen fit to explain why. It wasn't that he was worried, it was just that he'd been promised a real fight with Ichigo after their sparring match the other day, and he was getting antsy to get on with it.

"'Indisposed' means he is ill," that smug, superior, stick-up-his-ass Commander oh-so-helpfully explained.

"I know what the fuckin' word means, Kuchiki. I'm askin' ya what's wrong with him," Grimmjow said, his tone flat because that was better than a snarl—he knew full well that he was more pissed about this than he could justify. He'd taken a liking to the orange-haired kid, that was all.

"Do you give out confidential medical information to anyone who asks here on Hueco Mundo?" Kuchiki returned, and okay, that was fair. But…

"If he's caught somethin', he oughtta be down here in one of our hospitals. We got some weird shit here; yer doctors won't know how ta deal with it," Grimmjow responded, quite sensibly if he did say so himself.

"We've ruled out the possibility of infectious disease," Kuchiki said, and that was good, at least. Who knew what some kind of Hueco Mundo illness would do to one of this lot that picked it up. They were biologically close enough that it was possible, but different enough that the results would be unpredictable.

Wait. "'Ruled out the possibility?' That means ya don't know what's wrong with him!"

"I can't tell you that," Kuchiki said, but the slight widening of his eyes told Grimmjow that he'd realized that he made a mistake in his phrasing. Gotcha, asshole.

"Well, I'll come up an' see him, then," Grimmjow tried. Okay, he was getting kind of worried, now. Just a little bit.

"Impossible," Kuchiki replied. "Our CMO says no visitors."

Grimmjow didn't like that. If it wasn't anything infectious, then why the restriction? Maybe Kuchiki was lying.

"Then how 'bout we send somebody from our hospital up there? They can talk ta yer médicos, maybe help out," Grimmjow offered. Getting some trustworthy eyes up there might actually be better than going himself, since a doctor would know what was going on better than he would.

"I assure you, our own physicians are more than qualified. I'm sure Kurosaki will be able to see you soon, if he so wishes," Kuchiki said, closing the discussion.

Grimmjow was downright pissed at being stonewalled, but he'd done enough of this diplomatic shit in his life to know that there was nothing he could do. Ichigo had better not be so sick that they couldn't have their rematch before the Shinigami left.

"Alright, alright, whatever," Grimmjow said, giving in. "Well, tell 'im I said ta get back on his feet so he can fight me for real."

That errand completed, albeit unsatisfactorily, Grimmjow continued with his lunch break, now in pursuit of actual lunch. What the fuck was wrong with Ichigo, he wondered as he headed down the street, away from the temporary Shinigami consulate and towards his favorite cafe.

It wasn't any kind of bug, or so Kuchiki had said, but apparently it wasn't some normal Shinigami thing, either, if they couldn't figure it out. Ichigo had said he was of mixed heritage—Shinigami and, what did you call it, Human—though, so maybe that was making it confusing for them. Either that or Kuchiki was lying about him picking up something here.

He'd better not be, Grimmjow thought darkly. Ichigo was the most interesting of these visitors by far and Grimmjow would be majorly pissed if something happened to him. He seemed less alien, somehow; less devoted to order and boring formal stuff than his fellows. There was also the fact that while the rest of the visitors struggled to hide their fear and distaste for the Arrancar, Ichigo apparently just didn't give a fuck.

Had Ichigo seemed sick, the last time he'd seen him? That had been at the last fancy party in the seemingly interminable series of fancy parties the Shinigami had thrown in an attempt to woo the high-ranking Arrancar. They'd hardly interacted—Ichigo had been expending considerable effort trying to win over the undecideds. Despite the circumstances, Grimmjow had to repress a snicker—he could just picture Ichigo being all earnest at that emotionless bat Ulquiorra, to no avail. What an impossible task.

When he and Ichigo had briefly spoken, he had seemed somewhat preoccupied, but at the time Grimmjow had just put it down to the fact that he was keeping company with the World's Biggest Downer, Mr. Delusions of Grandeur, and the Colonial Control Freak for the evening.

He hadn't analyzed it too much because he had been preoccupied that night as well. Every once in a while, he thought he caught a hint of an out-of-place scent on the air, the sweet pheromone musk of el juramento—and for someone like him, there were few scents more distracting.

It made no sense, though, since there were no Arrancar men anywhere near young enough there—at such a high-powered gathering, even the waiters were the senior members of their profession. And it was just odd, to catch such a scent at random—anyone with any sense wouldn't be out and about at such a time. It's just not done, for one thing, and it's not safe, for another.

He'd seen nothing else to do but dismiss it, guessing that maybe a chance combination of scents had mimicked that one, or perhaps it was a deliberate emulation in the shape of a very risqué perfume. He shook his head, frustrated—he'd been too distracted by both the scent itself and the mystery of its origin at the time to recall much about Ichigo.

Grimmjow stopped abruptly, struck by the juxtaposition of ideas. Ichigo; that scent… It was a strange coincidence, that Ichigo had become 'indisposed' just when such a man, if he had existed, would have started showing signs in earnest. Mixed heritage; Ichigo said he had mixed heritage, Grimmjow thought with growing alarm. But surely he would have said if part of that mixture was Arrancar, wouldn't he? Unless he'd been ordered to keep it secret for some reason…

Grimmjow immediately turned around and headed for the Office of Interstellar Travel. Lunch could wait—he had to find out if any of his people had been on Earth when Ichigo was conceived. Except he didn't have any idea when to start—he didn't know how old Ichigo was. El juramento usually hit around seventeen or eighteen, but it could be delayed if the circumstances weren't right, and with someone who wasn't a full Arrancar, who knew what would happen.

Ichigo was young for his position, Grimmjow did know that, apparently considered as something of a prodigy, but that wasn't nearly enough information to be any real use… Fuck this, there was no way to figure it out. Shinigami, Arrancar, and Humans all had very different lifespans and patterns of aging, and if Ichigo really was a mix of all three or even just the two, there was no guessing his age from his appearance.

Or wait, didn't necessarily have to be talking about one of Ichigo's parents being an Arrancar, anyway; they could be talking about his grandparents, or maybe even the great-grandparents. Would the disposition for el juramento breed true, if Arrancar blood was that diluted? He had no idea. No other species that they associated with—other than the Hollows, on occasion, and nobody wanted to have sex with one of those—was biologically close enough for interbreeding, so it wasn't like he had any other half-breeds to compare with.

Agh, how was he going to figure out when to look? The idea that Ichigo could be undergoing el juramento right now was messing up his thought processes. If that that scent had come from his fair, soft-looking skin… No, he needed to think, to seriously apply his brain and think this through. Okay, so, what did he know about Ichigo's background?

Next-to-nothing, other than the fact that he'd been raised on Earth but gone to Soul Society as a youth. So, if he had gone there and been accepted, it was reasonable to assume that at least one of his parents was Shinigami. The other could have been either an Arrancar or a mix of Arrancar and human, or possibly the Shinigami ancestor was the mixed one.

What was he going to do? Those outlanders wouldn't know what to do about el juramento; they wouldn't even know what it was, and he didn't know if they could figure it out with the limited information they had. Their impulse would be to try to treat the symptoms with drugs, an endeavor that had never succeeded on Hueco Mundo despite centuries of effort. Ichigo would suffer for their ignorance—was already suffering for it, if he was thee days in and had no idea what the hell was happening to him—when he ought to have his commanding officer there to see him through and accept his oath of loyalty.

Ugh, his direct superior was Kuchiki—that was unacceptable. Besides, the trigger to end it, like the one that kicked it off, was pheromonal; likely a Shinigami wouldn't do. But then, if he explained what el juramento actually was, Kuchiki would fight tooth and nail against Ichigo binding himself to an Arrancar, even if that binding didn't hold much actual force. Ichigo himself would likely be too out of it to be much help, or even to properly consent. If he was right, this was going to be a diplomatic nightmare and a nightmare for Ichigo while they worked it out.

But he was getting ahead of himself. He had no idea if this was even possible; he'd never heard of any of his people going out that way, either to Earth or to Soul Society. There was certainly no guarantee he'd have heard of any such thing, though, especially since it had certainly happened before his elevation to Sexta Espada.

So the question was when and where he should start looking. From what he knew of the two worlds at hand, a lost (fugitive? Grimmjow couldn't think of any other reason to run that far) Arrancar would have a better chance at fitting in on Earth. Their society wasn't as regimented, and their population was way higher. Plus there would be fewer people around who could sense the difference between the newcomer's reiatsu and a normal Shinigami's.

So Earth it was, at least to start with. He didn't think a parent was likely—it seemed unlikely that the Shinigami military would let some kid with that big of a question mark in his history into their ranks. And a great-grandparent didn't seem like they would provide enough Arrancar blood for Ichigo to have inherited the disposition for el juramento—although he had no real basis for that assumption, admittedly.

So one of Ichigo's grandparents was the most likely suspect. Okay, but that was still a big time span considering he had no idea how old Ichigo was or how old his parents had been when they had him. Fortunately, as an Espada, he could requisition any records he wanted. It might take some time, but he could figure it out.

He walked into Department of Interstellar Travel's front office, scaring the hell out of their receptionist in the process. She was technically one of his underlings, as the Department of Interstellar Travel fell under the aegis of the Interstellar Defense and Exploration Fleet, which in turn fell under the massive umbrella of Defense and was thereby his a part of his bailiwick. Her alarm was understandable and somewhat adorable.

"Hello, welcome to…Sir!" she cried, her introductory spiel cut short when she recognized him. She stood, bowing deeply. "Good afternoon, Sexta Espada. How may I be of assistance?"

"I need ta know about any visitors goin' to a planet called Earth—yeah, it's a real original name, I know—between forty-five and mmm… let's say two hundred years ago, our dating system," he told her. It was, after all, possible that Ichigo aged like a Shinigami and was much older than he looked. Hopefully the long timespan didn't mean there would be a million records to sort through.

"Very good, sir. I can do that, sir. Records from that period indicate… only one match. Oh, wow; it's asking me for special clearance. If you could scan and sign, please, sir?" She held out an touchpad that he waved his ID at, then trailed a finger over it in his entirely illegible signature. It beeped happily. One match, huh? Well, at least this would be quick.

"Thank you," the receptionist said perkily. "Now then, the only visitor to Earth during the specified time period was a refugee from the establishment of the current governmental order, one of the last hold-outs from the previous power structure. One hundred and fifty-two years ago, Lord Emilio Tu Oderschank, commonly called—

"The Last of the Vastro Lordes?" Grimmjow interrupted, shocked and fascinated. "I had no idea he ended up there. The stories say he died at the siege of his fortress."

"According to this data, that is false, though a popular tale nonetheless. He and his family were given the choice to submit or flee by the Espada of the time because the then-Primera so admired Oderscahnk's abilities as a military leader. However, the Señora Tu Oderschank chose to submit and stay, so as not to raise the infant Señorita in a strange land.

"Lord Tu Oderschank left with only his lieutenant—a brazo derecho—and they both lived out the rest of their days in obscurity on the planet Earth. We received a communique from that brazo derecho forty years ago, informing us of Tu Oderschank's unexpected death and his own intent to commit suicide, as was considered proper in the old days."

Grimmjow whistled. No wonder that wasn't public knowledge. Señora Tu Oderschank must have put the alternate version about to protect her daughter Neliel, now the top aide to the Tres and considered likely to succeed her. It wasn't exactly cowardice, but any courageous option other than suicide had passed when the Espada had failed to kill him. It was pretty scandalous—the fact that he'd run off with his brazo derecho only made it look worse.

"D'ya know if he or his man fathered any kids while they were on Earth?" Grimmjow asked. Could he really have been right? Could Oderschank really be Ichigo's grandfather? "No; that's unknown," the girl replied.

"Thanks; ya helped me out a lot today, Señorita," he said, giving her a grin to cover his disappointment at the lack of answer. She blushed prettily at the praise from such a high-ranking official.

He started to turn away, but then said, "Wait, one more thing. D'ya know where he lived? The city or even the country?"

She consulted he screen and said, "Karakura Town, in a small but populous island country called Japan. It has a relatively high concentration of expatriate Shinigami, and apparently he passed as one."

Karakura, huh? That name rang a bell; something Ichigo had said. The recollection came to him with an image of Ichigo sitting beside him on a bench outside, his hair still damp from the shower after their sparring session last week, holding a bottle of water and looking relaxed and happy. Ichigo had remarked that he always appreciated the chance to open up a little with his powers because he always had to keep them locked down tight as a kid, that while his friends could roughhouse to their hearts' content, he always had to be careful. Grimmjow thought that sounded awful, to grow up among people with no spiritual powers, and had said as much.

"Nah, it wasn't so bad," Ichigo had replied, "In Karakura Town there were a lot of futatsu-futatsu; half-and-halfs, so wasn't so weird. Most weren't able to fully call up their zanpakuto, though. I guess having a little, long-ago dash of Shinigami blood on my mom's side, too, made all the difference. Or maybe it was 'cause my dad used to be a captain; most of the other kids' Shinigami parents were academy drop-outs."

Yeah, Grimmjow thought, or maybe it was because you weren't a half-and-half at all. Maybe you're not even a quarter human, Ichigo. He'd forgotten about that part of what Ichigo had said; now he knew that if his suspicions were correct, Oderschank would have had a daughter by a part-Shinigami Human woman, who had in turn fallen for a Shinigami captain and become Ichigo's mother.

That was really a damn impressive pedigree. Lord Tu Oderschank was a remarkable historical figure; a genius tactician and one of the very, very few—one or two per generation, if any—Arrancar with a second-level Zanpakuto release. And Ichigo's dad was a Shinigami captain, which he'd learned was the top tier of their fighting force—there were only thirteen of them, and they were the thirteen strongest people on the entire planet of Soul Society at any given time.

When they'd fought, Ichigo had said that he couldn't go all-out for fear of wrecking the gym. Grimmjow had suspected him of exaggerating at the time, but now he thought that he believed him. He wondered if in fact it hadn't been the whole block that would have been endangered, if he really was Tu Oderschank's grandson.

Oh man, did he ever want to take Ichigo out to the desert where they couldn't do any harm (except to each other) and see what that kid could really do. He'd heard the rumor that Ichigo had the ability to do a Bankai; like that, he would be able to withstand it, at least for a time, if Grimmjow let Pantera off his leash. The promise of being able to go all-out for the first time in a long time was enough to make him practically quiver with anticipation.

But he was getting ahead of himself again. First, he needed to confirm his theory, although at this point it would be a damn big coincidence if he was wrong. Then, he needed to explain to Kuchiki and the Shinigami médicos what was happening to Ichigo. After that, he'd have to negotiate for an Arrancar to see Ichigo through this. He should probably present a selection of candidates for the Shingami to choose from on Ichigo's behalf, or for Ichigo himself to choose from if he was lucid enough.

Normally, Ichigo would have previously agreed to his commanding officer taking part if he was in the military, or if he wasn't, he would have chosen an older friend or mentor to stand in. He probably ought to pick some military guys that were just above the equivalent to Ichigo's rank? Not that he knew what that even was, but he could find out. He'd never heard of a situation like this happening. He was sure there were legal precedents for what to do if there was no prior agreement, but he didn't know what they were or how relevant the Shinigami would find them.

Who could Grimmjow trust to treat Ichigo well, both in this time of vulnerability and after, if he decided to stick around for a while? According to the ancient military tradition, accepting a subordinate's juramento was almost like a sacred trust, and outside of the military it was a great honor to be chosen by a student or friend, but Ichigo wasn't any Arrancar's subordinate and he had no friends here. As a people, the Arrancar weren't terribly xenophobic, but he still had some concerns about what officer would completely accept the oath from a man who wasn't one of them.

And who… who could he nominate to be the one to put his hands on Ichigo's lithe body? To kiss his soft lips that must be red and swollen from being bitten right now? To enter and claim him; to accept his oath of loyalty and be accepted by his body?

Realization hit him like a slap to the face. There was no way he was going to allow anybody but himself that privilege. No way; absolutely fucking not. Just let Nnoitra or some arrogant young up-and-comer try it; he'd make sure that they could never play the part of fideicomissario again. Some part of him had accepted Ichigo as his, as his man, his subordinate, the same way as if Ichigo had been some fresh-faced, green brat newly assigned assigned to Grimmjow's squad back when he was just a sergeant. Grimmjow protected his own—be it from the enemy or from the greedy hands of interlopers.

He knew it wasn't his right to be Ichigo's fideicomissario; that Ichigo was in no way whatsoever his subordinate. His reaction was instinct superimposing itself over a modern situation where it didn't apply, but knowing that didn't make the feeling go away.

He genuinely liked the young envoy; before this, he'd hoped that perhaps they could become friends or maybe even lovers, if Ichigo ended up being posted to the embassy Soul Society was planning to open. He knew that this turn of events might have destroyed that faint possibility; assuming Grimmjow could convince the Shinigami to let him be a fideicomissario this one last time, there was the possibility that Ichigo, once he had recovered, might think of this as a violation and hate him for it. Even if he didn't, he might find the unequal footing that el juramento created so distasteful that he couldn't bear to continue any kind of relationship.

Even so, Grimmjow couldn't bear the thought of letting someone else see Ichigo like this; touch him like this; couldn't bear for Ichigo to become someone else's. If Ichigo didn't reject him, Grimmjow would gladly take him on as a sworn man, chain of command be damned. Or something; this wasn't the old days where the bond of el juramento was respected absolutely. They could work it out.

There he went, getting ahead of himself again. The odds were in his favor after confirming Oderschank had ended up in Ichigo's hometown, but be could still be mistaken. Seriously, he was going to feel like such an asshole if he was wrong about this.

Okay, time for action. Talk to the Primera first, or go back to Kuchiki? Kuchiki, he decided, and he'd ask to speak to the médico in charge of Ichigo's case. If he really had it right, then he'd go to the Primera, and they'd all have to have a big meeting. He could bring in some guys from the university to explain about the nature and history of el juramento to the Shinigami more articulately than he ever could.

He made his way back to the temporary consulate where Kuchiki spent his days, trying not to imagine how Ichigo was doing right now; especially not what he might look like. This was too serious of a thing to let his own desire affect his decisions, but he couldn't say he hadn't noticed how attractive Ichigo was. Imagining him lying in bed somewhere up on that ship, likely naked, flushed and panting and desperately aroused, the hair at his temples damp with sweat, eyes filling with tears of frustration as he jerked himself off for the umpteenth time…

Oh, that was not conducive to clear thought at all. That wasn't even conducive to maintaining basic decorum while walking down the street. Not that he really cared about decorum, but still.

El juramento was a serious matter, but it was also a major focus of the very concept of the erotic among his people, the subject of thousands of novels and stage or film dramas, plus thousands more works of a less highbrow nature. One of Grimmjow's personal favorite dirty movies was based around it, in fact. It was so… pure, somehow; so raw. Nobody could hang on to their hang-ups in the face of biologically hardwired need, nor could they in the face of such an uninhibited partner soaked in that unbearably arousing scent.

Oh, Ichigo, he thought, just wait a little longer.

It actually gave him pause, how much he wanted Ichigo—their collective cultural sense of the erotic aside, it wasn't really right for the fideicomissario to lust after his empujador too much. Things like looks and the kind of chemistry he had with Ichigo were not really what el juramento was supposed to be about.

In and of itself, the presence of pre-existing desire wasn't so bad, but it was somewhat frowned upon because it smacked of the fideicomissario neglecting to focus on his empujador properly because he was too busy slaking his own lust. That was unacceptable and a breach of the bond of trust that was meant to connect them.

However, Grimmjow was certain that he had the right feelings as well as the wrong ones. What would be really bad was if he didn't care at all; if he didn't feel like Ichigo was his—not in the sense of an object, but in the sense of a person who would become an important and trusted subordinate. Treating another's juramento simply as an opportunity to get off was universally condemned by Arrancar society because it was so easy to take advantage in such a vulnerable time. It was meant to be a taking-care-of; a seeing-him-through—it wasn't about the fideicomissario's desire, it was about the empujador's needs.

So maybe it would be better if he hadn't already been lusting after Ichigo since well before this began, but he had and he couldn't change that. He didn't think that it would interfere with his duty as fideicomissario. He'd have his fun, but he'd take damn good care of Ichigo. That would be his number one priority, and he was going to get it so right that Ichigo would remember how good Grimmjow made him feel for the rest of his life.

Now he just had to convince everyone else to let him make it happen.