((This chapter may ramble a bit, but it was meant to be that way since it's very introspective.))
He wasn't very interested in it, of course.
Ulquiorra could feel the explosions of their reiatsu clashing, Jeagerjaques and Kurosaki clashing over and over again in a mad beat. There were now two options, two courses of action he could take at that moment in time.
One: Head over to the battlefield, kill Kurosaki right then and there.
Two: Wait for orders from Aizen before acting.
...There were three courses of action he could take at that moment in time.
Three: Do what Orihime had been requesting of him.
He was conflicted on which idea would be the most prudent course of action. Aizen had ordered them to wait for Kurosaki and the intruders to come to them, and not to seek them out. But, they weren't that far off either, and Aizen would most likely not want to lose his Sexta Espada. If Grimmjow were even going to lose at all. Aizen was probably not going to bother with orders, actually, since he was...occupied at the moment. He may be anticipating Ulquiorra to go ahead and take things into his own hands, of his own free will.
That begs the question of if Aizen even thought that Ulquiorra Cifer has any free will at all. He did. He just didn't think it was useful or needed, not before. Now, as he lay back on the large couch with Orihime laying on his side (they were both clothed, of course; Ulquiorra was not willing to try something so wild and unpredictable as sex, not when he didn't know more about how to at least perform such an act), both staring blankly off into the distance and lost in their own thoughts, he began to wonder if Aizen had planned this relationship, too. Ulquiorra certainly hadn't. And Ulquiorra, meanwhile, was still attempting to figure out what this relationship is.
He did not know what love is. He did not know what that felt like, and so he did not know if it was 'love' or not that he felt for her. He didn't really think that it was, because if he were ordered to, Ulquiorra could and would kill Orihime. Love was supposed to be when you would be willing to lay down your life for another living being. That notion is insane. His life was more valuable than hers, to him at least. If she died then he could strip that sensitive section of his soul away and go about his life. Even if he did give his life to save her, whomever took his life would probably take hers next. That sacrifice would be in vain.
He did not feel lust for her body. Though he did have sexual urges, he didn't need to satisfy them and barely even felt them anymore. Neither of them possessed the maturity in that area to take their relationship, whatever it is, in any physical manner beyond stiff, near robotic kisses and lying relatively close together. It would have taken a very long time for Orihime to even trust him enough not to leave her, abandon her like all her friends did, and it would have taken an even longer time for Ulquiorra to reconcile whatever he was experiencing for her.
This relationship they shared was not romantic, not in the least. It was sterile. Stiff. Inhumane. They weren't whole people anymore, and they couldn't pretend to be; there would be no sweet nothings whispered in her hair, or any admonitions of love for him. They weren't capable of saying those things. Sure, they could attempt to, just to see if it sounded right on their lips, but it didn't. They had their dramatic moments where it almost looked like they were two young lovers, the dead Romeo and Juliet, but a look in their flat, dull eyes would prove quite the opposite. Her feelings for him were gossamer at best; she didn't adore him as she had Kurosaki years ago, she attached herself to him because, despite herself, she was still Orihime Inoue in some way or another. She needed an anchor in her life. She wouldn't dare allow herself to feel anything other than attachment to Ulquiorra at the moment, because this trembling notion of love was something she wasn't going to grasp right now, in case it withered away, but she was attached to him. He protected her those years, from Nnoitra, from anyone else that would cause her harm. It doesn't matter what he was like; he was there.
Ulquiorra's feelings for her were an odd attachment he was trying to sort out. He didn't have any clue exactly what he wanted about her, but there was something that he desired. He needed to find it. It isn't that he wanted to protect her of his own accord, at least, not in the beginning; she was a person he was supposed to protect and feed, and that was it. He didn't care all five of those years; what happened to change that? Nothing, that was just it. Nothing happened. That was what made no sense. She changed her personality, threw away her childish hope, and then?
Something is dawning on him as he lay there, staring at the ceiling with her arms crossed loosely around his neck. Something that may break his world.
He felt like he wasn't alone now. He wasn't alone in cynicism, he wasn't the only one that saw everything in blacks and whites and grays. She could see the word for what it was.
She could see it now.
She was a hollow of a human being. And she was devoted to him, in that tentative, almost frightened way that she reached out to him for comfort, for protection, for an anchor to the world.
Ulquiorra theorizes that they have both developed slow, almost unnoticeable syndromes. She may have found him her only tie to the world, her only protector, and slowly developed Stockholm syndrome for him. He may have found her a fragile, delicate and naive little child, but as her worldview developed and turned to his, he found someone who saw the world like he did, and developed Lima syndrome for her.
They are sick people.
"Ulquiorra, did you consider it?" Orihime asked him in dull tones, and he turned his head slightly, looking at her from the corner of his eye. He hesitated a moment, his mouth open slightly, before he feels Grimmjow's reiatsu dim. Nnoitra's clashed with Kurosaki's next, without missing a single beat, and though Grimmjow was apparently still alive, he was defeated.
"...Yes. I will take you."
They may love in some sort of hideous, grossly malformed way, but it is just that: an abortion of emotions that neither of them have.