I saw a picture and this was my conclusion. Feel free to bonk me on the head. Truthfully, I think it's out-of-character but you might think otherwise. Might.

i.
Orihime wasn't going to die a kiss virgin. She refused. As much as she loved Ichigo the fact she hadn't kissed a single person yet and her life was almost over was sad. She was young, yes, fifteen wasn't that old at all but she didn't want to die a kiss virgin.

So, she planned.

The only male that came up was Ulquiorra. She wasn't sure if she wanted to kiss him but she had a feeling he wouldn't kill her.

Well, at least not until Aizen let him.

So, she tried to convince herself that it would be a good idea and it wasn't that bad.

By the end of two days, she had done a damn good job and waited, squirming uncomfortably, for him to show up. She would not lose her resolve and she would do her best not to humiliate him. She would wait until the door was shut.

ii.
"I'm coming in."

It was sweet of him to warn her. She had told him he had scared her before. No! Now she was starting to interoperate everything he did as… Nice. She waited for the lesser arrancar to leave before looking at her food.

The stupid door was open. "Are you going to eat?" She saw her chance and quietly shoved her food away. He narrowed his eyes.

Now, for the pick up line. She was blushing before the words even left her mouth, "I'd rather have something else." She couldn't even look at him.

He was completely oblivious to her advance. "You don't have a choice. Eat." He stood, "If I return and you—"

"No! Wait!" He stopped to look at her and she panicked, dashing to block him from the door, "You can't go until-until-until—" She couldn't tell him, instead, her blush darkened. He did not look amused. "Please stay! I.. have to gather my nerve?"

He was still too dense to get it. This time, however, she was thankful for it. "What do you want, woman?"

She blurted out, without thinking, "Bean paste." Before he could comment, she said, "No! I don't mean that!" She shut the door behind her and realized it locked from the outside. Duh. She bit her lip, "Don't kill me!"

His eyes narrowed, "I have orders not to."

Right… She wondered how much force it would take to knock him down. And how fast she would have to be before he realized she was throwing herself at him—Ah! It even sounded wrong in her head. "You don't have a girlfriend, do you?" He blinked and glared at her in response. "Of course you don't…" She grumbled, "None of you do."

"Why does this matter to you, woman?"

At least he thought of her as a woman, right? It wasn't as bad as trash. It was at least one level up! God, she was pathetic. I can do this. For… not dying a kiss virgin! Then, with a strangled war cry, she lunged forward, knocking the arrancar to the ground.

He was lighter than she had thought and it hadn't taken much to throw him down. Probably because he had shifted to move forward.

Before she could convince herself otherwise (or die) she smashed her lips onto his. She gripped his wrists, trying to keep his arms down and noticed he didn't fight. Probably too shocked. Probably getting very, very mad.

In fact, he wasn't even breathing.

Great, she felt like a rapist now.

That didn't stop her trying to do what people called 'real kisses.' She felt terrible and wasn't sure how to do it and when reading, she normally got too flustered to continue. So, she prayed for help, and licked his lip.

It was gross and yet somehow pleasurable at the same time.

He, however, either didn't appreciate it or finally snapped out of his shock.

She went flying off of him.

His eyes were cold, "Do not try to throw your affection for the shinigami trash onto me, woman. My orders say nothing about punishment."

She bowed her head and squeaked, "I'm sorry, Ulquiorra-san!"

The door slammed behind him.

When she was sure he was gone, she smiled. He tasted good. And wasn't so bad, really. And he hadn't punished her even though he said he could've. Really, he was quite attractive, too.

Then, her face fell. "I wasn't thinking about Kurosaki-kun at all. I-I was—How can I even say I like him! The enemy of all things! Bad, Orihime, bad!" She hit herself on the head and cried. Because really, she hadn't thought of Ichigo since she began to play with the notion to kiss her captor. What kind of sick person was she?

Little did she know Ulquiorra was right outside her door, quite surprised by her verbal outburst. So she wasn't thinking of the shinigami.

iii.
It became awkward after that, though Ulquiorra didn't seem to change.

She kept waiting for him to grab her by the hair and beat her to a bloody pulp. Or worse, let Nnoitra have her.

And Ichigo… What would he do when he found out? She didn't want to think about it. Her selfish actions had been unacceptable and it was too kind of Ulquiorra to pretend it had never happened. So, she tried to punish herself. By throwing herself against the wall. Over and over again.

Ulquiorra did not approve.

"I'll tie you up to a chair if you continue and gag you if you wail." She didn't doubt it.

But that didn't stop her.

So he grabbed her during one of her sessions and growled, "I warned you." And she was tied to her chair. "I realize you're doing this out of guilt, woman, but you belong to Aizen-sama not that… Trash." He spat out the word like it was even more degusting than usual and she blushed. "Unless you're having disloyal thoughts."

She was terrible. She couldn't be loyal to anyone.

So she broke down.

"Woman, stop crying." Sob. "Now." Choking on tears. His tone changed to the closest thing to pleading he could make while still sounding unemotional, "Woman, stop." Of course, it didn't work.

"I am being disloyal to Aizen!" She wailed, "And Kurosaki-kun! And Soul Society! And Kuchiki-chan!" She listed pretty much everyone she knew, including Grimmjow and Nnoitra, before crying, "And even you, Ulquiorra-san! I can't be loyal to even you!"

He was silent. She wished he would yell at her.

Then, quietly, he growled, "You should only be loyal to Aizen-sama."

He untied her, leaving, and she fell into the bed. She would be loyal to someone! And… It was too late for Ichigo. So she would be loyal to Ulquiorra.

iv.
He didn't bring up her break down.

Or the kiss.

She kept waiting for it but it never came. And, apparently, Ulquiorra had resolved never to talk to her other than telling her to eat. Not like he talked much before but it was worse. All he ever said was 'eat' and he knocked before coming in.

She decided to see what would happen if she kissed him again. After all, she had kissed him before so really it wasn't like she had a first kiss to save anymore.

She was waiting when he came with lunch, "I'm not going to eat today." She met his eyes, letting hers flash with a challenge. "I've decided who I'm loyal to and it's not Aizen."

He shut the door behind him and met her with a cold glare.

He wasn't ready for her charge.

He didn't fall this time.

"Who is it, woman?" He snarled, "Your friends plan to come here. They'll die." His cruel words almost broke her resolve. Almost.

She had another thing to try. She placed a kiss on his hollow hole and, though it was cold, she could almost feel something in it other than the emptiness. It wasn't pulling so much as pushing and it hummed a bit.

Ulquiorra reacted by letting out a strangled cry. But, she noticed, he didn't push her away. He leaned towards her.

And then left in a speed she had yet to see.

v.
He returned later, eyes actually filled with rage, "Who are you loyal to, woman? And don't try to distract me." If that's why he thought she had done that it must've affect him quite a bit. Like, more than quite a bit. A lot. "Answer."

"If I do, you might leave."

His eyes flashed with even more rage. A storm of green. For some reason it reminded her of lightning though the reason was a mystery. "Why would I leave? Still the shinigami trash? Are you becoming a whore?"

She wasn't offended. That had just proved how deeply she had affected him. "No. And you'd leave because… well, because you just would."

He snarled and grabbed her throat, "Who is it?"

She bit her lip, "No."

He tightened his grip, "Tell me."

Really, he was a terrible person. No, not even a person. He was a monster. A monster but she had chosen. Her voice was strangled, but he heard, "You."

He dropped her and left.

She laughed bitterly, "Told you you'd leave." She froze. Bitter? She couldn't be bitter! What was he doing to her? What was she doing to herself?

vi.
He didn't return, a lower arrancar brought her food alone. She felt like crying but accepted the punishment. It made sense, after all, and she really did deserve it. Then, she felt him return. She could sense him now, she realized, and found that she was fine with that.

Orihime was getting stronger after all.

He entered the room and glared down at her, "You are loyal to Aizen-sama."

So, he was going to try that. "You."

"Aizen-sama."

"You."

He scowled, "If you were loyal to me, you'd be loyal to Aizen-sama."

She shook her head, "Only you." The less people she was loyal to, the less she could betray. She didn't think he would understand her reasoning, "If I'm loyal to you and Aizen tells you to tell me to do something I'll have to do it."

"And if I command you to follow his orders at all times?"

She bit her lip, "Then… I'll do it. Unless it hurts you."

His eyes became guarded again and he turned to leave, "Then those are your orders."

"Will you come back later?"

He didn't answer.

vii.
He did come back. But with Grimmjow.

She wasn't sure if she should've been horrified or annoyed.

So, she chose to be the former.

"Feh, what's with the face? Not like I'm gonna kill you."

Not even those words would lesser her fear. Instead, she grumbled, "He brought a body guard." And then, Grimmjow seemed really interested. His eyes lit up and he looked over at Ulquiorra, grin widening. She blushed, "Oh no, it's nothing bad! At all! And he really can protect himself! Really!"

"What have you been doing to Aizen's lapdog?" She felt faint. She had embarrassed him and herself with that stupid comment.

"N-N-N-Nothing!"

His grin grew and, really, it was probably the most terrifying smile she had ever seen. "You know, you can tell me. It's not like he's going to stop you. Or, even if he did, obviously if you think he had to get a bodyguard—"

"No, no, no, no! I just said that because I thought he wasn't wanting me to—Nevermind."

"Tell me or I'll kill him." She blinked. Ulquiorra was stronger, wasn't he? And how could he just take these insults? "Maybe I should lie to Aizen about—"

"I've jumped him!" Her eyes widened and she covered her mouth. "Wait! That's not—" Grimmjow's laughed drowned out her explanation and she gave up, avoiding Ulquiorra's eyes. He was probably mad. Really mad.

Damn it.

viii.
Again, Ulquiorra didn't bring up any of the things that had happened. Not even loyalty.

She was getting sick, too. The fever was setting in.

Well, she had thought she was going to die. Just not because they didn't have modern medicine.

ix.
She woke up with Ulquiorra pressing a cold washcloth on her forehead. He said nothing and she relaxed, feeling the fever subside. "You will remain loyal to me?"

"Yes."

"Then tell your friends to leave."

She stiffened and realized he was waiting for a no. But… She had pledged loyalty to him. "Yes, Ulquiorra-san… But… Can I sleep a little more?"

Instead of answering, he pulled the covers closer to her chin and left, leaving behind the wet cloth.

x.
"Ku-Kurosaki-kun, you h-have to go."

"What?"

It hurt but she had already betrayed him. "I… I'm working for… I…"

Ulquiorra stepped forward, saving her from having to say those horrid words. "She has chosen to stay, shinigami. Leave."

Ichigo began to pull out his sword, "Like hell I—"

Tears falling down her face, she cried, "Don't hurt him, Kurosaki-kun! Don't… Don't hurt him!"

"Inoue—"

"You're hurting her." His tone was icier, if possible, as he addressed her former love. Former, because she had to move on. Even if it hurt, she was doing it. "She's staying so go before I'm forced to take action." It was perhaps her tears that got the boy to go or maybe it was the grimacing Ishida. Whatever it was, it brought a slight weight off of her chest. "Come."

She obeyed and was surprised when he turned around and pinned her to the wall. "Ulqui—"

He pressed his lips to hers. He still seemed distant but the action was enough to give her hope. He knew about how she was beginning to feel, he wasn't blind like Ichigo. Perhaps, with enough time, he'd return her love. He pulled back, "That was your reward." He avoided eye contact and she smiled.

"Thank you, Ulquiorra-san!" He remained silent and she took that as a good sign.

She wasn't going to betray him. Never. She would love him, even if she had to force herself to… But it was easier than she had thought. She liked how he was, in a way, and he protected her without her feeling weak.

And she would remain loyal this time. No matter what.

See? I think it was OOC, but maybe it wasn't too bad.