The difficulty with the plan, Ulquiorra made clear, was the same difficulty that arose with all seemingly obvious solutions: it wasn't that it wouldn't work, it was that it was more complicated than it seemed, and the repercussions in the likely even of failure were all but unriskable.
The Hogyoku existed in several planes of reality at once, and summoning it in its entirety to just one required a surge of effort from its handler—in this case, the already seriously weakened Aizen. And, Ulquiorra warned her, even if Aizen could summon it in his current state, the other Espada would feel the power surge from miles away and wonder what was afoot.
Orihime felt a surge herself, but of something more like excitement. It was like they were planning an interdimensional heist. And like any good heist, none of the players's cards were entirely on the table.
Aizen would have to be kept partially in the dark. Orihime could tell the very notion of attempting to manipulate Aizen was giving Ulquiorra fits, but she didn't know whether it was because Ulquiorra was just that loyal or because Aizen, as a master of subtleties himself, was just that likely to see straight through it. The fact that he was so low on strength right now just meant he was less distracted by things that might have otherwise been relied on to cover their tracks.
Ulquiorra ticked off the risks as they currently stood:
1) Aizen proves too weak to summon the Hogyoku, and the attempt further weakens or kills him. Risk level: unacceptable.
2) Aizen summons the Hogyoku successfully but it won't respond to Orihime's attempt to use it as a power source. Risk level: moderate, but likely to be compounded by:
3) The Hogyoku's summoning attracts unwanted attention and the other eight Espada either react with suspicion or take advantage of Aizen's weakness. Risk level: unacceptable.
They of course inducted Grimmjow into their fledgling scheme, and while he was enthusiastic enough to be getting up to something dangerous and uncertain and possibly at odds with Aizen's wishes, Orihime found herself sneaking glances between the two of them like Ulquiorra had once snuck between her and Grimm.
Normally they would have fired shots back and forth at each other and kibitzed over every little thing, but Grimmjow was quietly ecstatic now when Ulquiorra appeared uninvited in the tower that night, eyes sparking but without the pain and conflict she'd seen in them before. Meanwhile Ulquiorra became even haughtier, as if trying to seem as chilly and composed as he once had. She found herself looking for any reason she could to tiptoe away to give them space, though she couldn't have said exactly what she was hoping they'd do with it.
Meanwhile, they had to maintain appearances—for a little while longer, anyway. The Espada had eyes and ears everywhere, but now they had to maintain a semblance of normalcy with Aizen as well, even if that normalcy was the healer's equivalent of the push-me-pull-you game.
Orihime went back to him the day after pulling Grimmjow into the scheme and did another round, but when she braced to have some heavy dropped on her by another vision—either more sex or more intrigue, but of which caused her different types of discomfort than they did at first to—this time there was only a sense that she was running out of material. The visions were trickling to a stop, as if they'd shown her everything they had to show. And yet, Aizen was not healed.
He was sitting up when she came in the next day. That was progress, but it also wasn't. The display of rigor clearly cost him more than it was worth when he had no audience but her and Ulquiorra to front for.
"Hey," Orihime said, a smile quirking her lips. Uli must have heard the fondness in the smile, too, because he cocked an eyebrow at her. "What are you doing up?"
"Maintaining appearances," Aizen said with a pained grunt. "You're working so hard, I should at least try."
"I mean this in the gentlest possible way," said Orihime with a grimace, "but please don't. You'll only give me more to make up for."
Aizen met her grimace with one of his own and settled deeper into his couch.
"Fair enough," he said with a grunt as he laid back. His fingers flicked toward hers when she rested her hand on the pillows. She didn't move them away. In a moment more honest and less brave than she would have thought possible, she curled hers around his. He sighed, some of the tension flowing out of him.
"You know," he said softly. "This might sound odd, but I've been thinking you were mad at me since this happened."
Orihime couldn't help it—it took her totally by surprise. She barked a laugh, a sudden disbelieving shout, and Uli made a lurch toward her as if he was tempted to shake her. Aizen too raised his eyebrows.
"Sorry," Orihime said quickly, abashed. "Sorry, it's just—no, I um. I've been worried. That's all."
Aizen made a face, a particular face that somehow Orihime knew well though she would have thought she'd never seen it before. The face said "don't try to lie to a liar."
"I mean," she added, patting his hand as she tried to think on her feet, "okay, maybe my toxic trait is getting angry at people when I'm worried about them. But yes, I have wondered if—" she swallowed and forced herself not to look at Ulquiorra for cues. It would almost certainly give them away. "I was wondering if maybe this was your fault somehow. I'm sorry, but I was."
"Blaming the victim," Aizen said with ironic good humor. "Never would have thought it of you, Ori."
Orihime almost agreed, but then she reconsidered. She didn't think Ori—the other her who Aizen seemed to know so well—would have been above such a thing, necessarily. She risked an answering ironic eyebrow.
"Wouldn't you?" she hazarded.
Aizen's ironic smile widened. Moments like that, she thought, he gained back some of his villainy. She realized that Ori's harshness, her cruelty and lack of tact, was part of what drew him to her. Orihime felt a flush of inadequacy and sadness, and even a sense of loss, at the thought. She was flexing a bit of a devious side lately with all this scheming, sure, but that hard, certain, furious part of Ori felt as foreign and impossible to access as the prospect of sprouting wings and flying away would have.
A tiny glance flicked between Aizen and Ulquiorra, and for a moment Orihime worried some wire had tripped, but Ulquiorra only nodded and backed away, around the partition within the room. Aizen wanted privacy with her, she realized. Her heart skipped a beat as, for just one traitorous second, she hoped he would take the opportunity to kiss her.
"If we're being honest," Aizen said, and Orihime felt another twist of anxiety wondering if he was still being ironic, "I'm fairly certain it's both of us."
Aizen waved a hand over his sternum in an odd gesture. Orihime reached for his robes, already slightly parted to reveal his collarbones and a handspan or so of firm, unmarked skin, before she suddenly caught herself and darted back. Something was moving under the skin of his chest.
A blot of darkness, a simple, slate gray faceted jewel, rose to the surface of his skin. It was like watching a bullet make impact in reverse. The skin around the object pulled and puckered painfully, though no blood spilled around it.
It was the Hogyoku. She'd only seen it the once, that first day in the court, but she'd never forget it. She stared at it. It was practically under her fingertips.
"This was," Aizen said wearily, and shook his head, "not one of my better ideas. I just didn't know what else to do. Things were destabilizing left and right—the Espada were jockeying, eyeing me up in the downtime, and I knew someone was going to make a play. I just couldn't find out who. I had to hide it. And nowhere was safe enough."
Orihime was speechless. It was right there. Had been, this whole time. Right where Aizen's heart should have been. She could have been picking at it all this time, but instead she'd been mired in this back and forth energy game, all while it was for all intents and purposes killing its host.
She realized with a jolt just how badly she wanted him to live. It flipped on like a switch, like that other part of her under her skin had suddenly turned her head and looked too, and now both were finally in alignment.
"When…" Orihime breathed, and didn't know how or if she should finish the question.
"While you were gone with Grimmjow," he answered. He sighed but his breath was already coming easier, as if he'd been having trouble breathing around the thing this whole time. "I didn't tell you because I was afraid what would happen if anyone found out. So it's not your fault. You couldn't have known. I've been thinking it was some kind of reaction, the day you came to visit me and we got close for the first time in so long—but I still can't imagine why it happened. It should have been in tune with us both. I took every precaution I knew to take. I even gave you—" his shoulders shook briefly in a mirthless laugh, "well, you might call it backend user access. Admin privileges, so to speak, as equal to my own as I could make them without actually putting it under your skin."
Orihime's brain was ticking over the problem now, both sides of it at once. Aizen continued.
"I need to ask you something," he said, and she braced. He looked pained, but not physically. "Did you—did you reject something that day? Something about me?"
Orihime didn't answer. They only stared at each other: him at her face, her at his chest.
If she'd been able to answer, she would have said she'd rejected herself that day.
Aizen's Ori, she'd decided. She'd rejected Ori, and something had split off from her that must have been integrated before. Not faultlessly, not seamlessly, but close enough to function. But some faultline had still existed, and when she'd rejected Ori that hairline fracture had shattered, leaving boneshards to drift—painful and deadly—through her emotional bloodstream. These visions she'd been having, this other presence, screaming at her, taunting her, stranding her in impossible situations…
Aizen kept talking, as if to soothe her.
"Maybe it was just instinctive. I knew how you felt about the thing. I should have told you before we—got close. But it's a part of me now. Who knows, maybe it always was. I gave up enough to make it, so it certainly felt like it. But it's not just symbolic now. Now if I—or even you, it seems—reject it, I fall apart, too."
Aizen smiled weakly. Orihime was finally able to look away from his chest long enough to see it.
"You made yourself the housing around an atomic bomb," she said at last. Her voice had a bland, shell-shocked, musing tone to it. And gave me the launch codes.
"Quite so," he said, chagrinned. "Removing it would be disastrous. I've already considered whether my dying will solve the problem." He grimaced. "It won't. I'm relatively certain at this point that without me to stabilize it, the Hogyoku would just siphon everything it ever made back into itself. More or less this whole world, and a substantial part of yours too, would simply cease to exist. "
They were quiet a long moment.
Ori," Aizen said, "I'm so sorry."
"Me, too," Orihime said. "I am, too."
She had no feeling in her fingertips or her heart. She had no idea what she was going to do.
But she thought she knew who to ask.