Ngoc Chau does not own Bleach

Okay, the reason why I went with this path is because it's still incest. It's still his blood in her and thus it makes her his daughter. Everyone knows it like that. Plus, you don't exactly see them doing anything romantic during the series. They both seem pretty indifferent to the other romantically and serve more as comic relief throughout the series with the occasional "Let's get dangerous" battles. So, this is part 6/12 of Consideration. I was inspired to do this from reading volume 14 of Bleach or volume 15 of Bleach after the battle between Kurotsuchi and Quincy. Mayuri himself had called her his daughter and Nemu even added that because she was his daughter and her blood was essentially the same as his, his poisons wouldn't harm her as it did for everyone. So that got the gears in my head spinning and this is what I came up with. Originally, this was supposed to be a stand-alone until I thought it would be a good installment to the Proposal String

Part 5/12 of the Proposal String

Prompt: Poison

Kurotsuchi Mayuri realized as soon as the words left the Soutaicho's lips, "It is not as though we doubt your affection for one another. However, this marriage cannot be allowed as it imposes upon incest."; that he had basically screwed himself over in trying to protect Nemu.
The one time he had thought of someone else and it goes nipping him in the bud! Worst was that he had broken a promise he had make more to himself than to her. He wondered if she realized this: a part of him hoped that she wouldn't while another urged for her to realize it was already broken from the start. He could feel the disappointment from her coming off in waves, such was their bond to each other that they could often feel for each other, know when the other was sad or angry. How beautiful their empathy was that he could feel her fear, her pain, her joys, her prides… Even better was that she was able to tend to his sadism. How much more it proved that they were meant to be together: that she could know every part of him, dark and light, and accept it. And for he to understand her, no one else understood her as he did. They thought they could use logic to figure out a woman like her, there was simply no dark corner or spot of her mind that he could not infiltrate into. However, it was really no loss: she was as much wife and daughter to him as any woman or girl could be.

But it was that feeling of disappointment, that everyone should know about this weakness of his for Nemu and that he should have nothing out of it, be robbed of what he wanted. He had unwillingly fallen in love with another, he hated himself for feeling such and hated her as much for encouraging him. It was knowing that there was evidence of his weakness and it could be used easily against him, one way or another. No plan was perfect and no one was perfect: everything could ruin better and common sense, he was no exception(Though, Reader, he was much more aware of facts than most people, yet still he was no exception to the chance of someone, someday, taking his daughter away from him and using her as a tool against him. No necessarily as a weapon but taking her apart to pieces to know secrets of his that he had hidden inside her shell). But he could not help himself.
It had happened before, Pygmalion fell in love with his own creation that he made with his hands. Nemu was weak and aimless, asking stupid things often and doing stupid things; she could simply not function without him to guide her, she needed him to survive. In that need, he had pitied her and gloried in it, to be needed as air and water and food. No one had depended on him like that, necessary, and it soothed his much bruised ego.
He took her power, the power she gave him and called it his own, summoned it as his own heart. He knew and she knew that without him, she would die for good.

And everybody was wrong.

He didn't program her with no free will, she had to have had free will to make the experiment successful, that was the difference why the other gikons could be built to be just as intelligent and just as powerful as officer-class shinigami, but they lacked a zanpakuto. He had done what Urahara Kisuke had not been able to do: construct a gikon that could grow and develop its own zanpakuto, another being of the same heart.
And she loved him, despite what he did to her, she loved him. Everyday since her, he had felt her feelings for him as fear and worship - and he wanted it that way because it was exactly what she should be feeling as he had given her life, he could easily take it away - yet it transcended that through the verbal abuse, the beatings, and the surgeries. He felt it bud and bloom into something that he could not ever imagine feeling or having it felt for him. In that development, he had used her; he used her for his feats of modications and experiments to understand why she should feel the way she did because she was, after all and forever more, an experiment: a false being.

So he had taken her and cut her open alive and did whatever the hell he wanted to her and she bore it, never looking back but straight on. And it was still not enough for him to know yet not understand. He could not properly conclude it, he could only look at the outcome and declare it. Love. And yet not love. It was not exactly a true love, per se. It was more than that, that she could see through and inside him, and fear it and be in awe of it and hold it and be in thrall of it completely as something she should. He could not name it, because he was already barely familiar with human emotions besides the basics of fear(for this was one that he he knew extensively about and was profound in), happiness, sadness, worry, and anger. She should've felt something different than what she did from what he placed on her, but she had gone against the grain and felt something that he damned himself for being ecstatic over.

In his efforts to try and drive her away from him, to harden his heart to her advances and her looks at him; it had only made him worry for her more. That he had to keep her closer by his side, that those modifications should protect her instead of change her. And it made him despise himself all the more. How he could still fall to such primal human urges that he should have better control over by then.

She chose him just as much as he chose her, he wanted to tell them.

It was not entirely his choice: he wanted it and so had she and they both agreed for it to be mutual. As much as a sadist as he was, rape was not something he was actually willing to do(unless it served a good purpose such as revenge or much better reasons either than someone needing to simply get laid) for it showed a beast who could not think with the head on its shoulders; he was a scientist, god damn it! He was not so desperate a man that he would use someone for sexual gratification - self love served its purpose well in that category.
All he could think about was how differently the experiment - she - had turned out: how she was supposed to be unfeeling, but she could feel and was compassionate for others and had stayed loyal to him all on her own(though some of his 'teachings' had helped to enforce that within her).
Interesting, the word rang in between his thoughts. He wanted her always with him. She proved herself to be a more than capable lieutenant who could think and function just as well if not better than any other shinigami of high level and he knew that she would always obey his orders to a T unlike the others - they were just so afraid for their lives. And in the idea of protecting her and making sure that she could stand what he could stand, he used his blood as a basis for the body - the heart and soul belonged solely to her, though she gave the former to him.

Do not parents want to protect their children, daughters particularly because they are so in need of guidance? Will not husbands do what they must to ensure that their wives will survive?
Virtually every one of his drugs that had been developed from his blood would have practically no affect on any of them, his poisons would be obsolete only to the two of them. His blood, the same blood that protected her while killing everyone around them, flowed through the two of them. They may as well have shared a body, a liver, an eye… His similarities could be found in her as her own were found in him, his habits were embraced by her and her quirks were nurtured from him…
How was he any different from anybody else that wanted another to possess, to have someone who shared as much as possible with them?

The first time he had exposed her to his poison, he sat on a chair in the corner of the room and watched her with his arms crossed over his chest and interest bright in his eyes. She would have to survive, their DNA were one and the same that it could not have hurt her. And it did not. She had stood there in the center of the room, her long hair trailing downwards. She had looked at him with those green eyes that threatened to probe and dig if stared at too long and told him that she felt fine, a little trouble with seeing because of the smoke and the smell was a bit overpowering for her; but, all in all, she felt fine and indifferent to the poison.

They left the captain's meeting, there was nothing more to be said or done. He was not going to throw a tantrum just because they denied the marriage. He had already been humiliated enough by having all the captains look at the two of them before(especially now that the Kenpachi knew and word would surely be spoken). He was going to keep what was left of his pride and walk gracefully from it, no bad word and not even a thought to infecting all of them with new bacteria. But he was still rather bitter about how they all looked at him and Nemu, with those contemptous eyes filled with anger and disgust. What was the difference with how he had had her before and what he was going to do to her as soon as they got home? A brief thought poked him: were they going to take her away from him?
Outside, night had already come and taken the day's lights. The moon was full. The entire affair left him tired and he wished that he had known about this before instead of hoping that it would be made legal. He turned to her, her face was cast downwards. "Nemu." he snapped at her as they walked back to their barracks. His voice echoed everywhere and a small part of him feared that someone might hear and complain. Though that little part was quickly eradicated by another part of him who just felt pissed off and wanted to kill someone.

She looked up towards him and bowed her head slightly before bringing it back up, "Yes, Mayuri-sama."

He swallowed, his chest suddenly felt tight and he had to wonder if the new heart he had transplanted in him recently was not doing so well under all the stress that had been going on. "This… what they said… it doesn't change anything. Do you hear me?"

What didn't it change, Reader? What exactly, for Kurotsuchi Mayuri himself did not know what remained unchanged and what didn't. Perhaps he meant that their relationship as husband and wife would not change for them, that their fates were already intertwined together from the very first moment he held the test-tube in his hands or when she first took her breath of life. Perhaps he meant their position as captain and lieutenant: father and daughter?
Bitterly, he wondered how the hell could they have gotten their hands on the marriage document. Nemu had put it away and he had warned her not to mention this to anybody. But the fact that the soutaicho had the document in his hands then... he wondered just who had found out, just who had sold him out, how long had they held onto it before giving it up... But he swore that if he ever found the person responsible for revealing it, what he planned would only make the experiments he did on the Quincies pale in comparison.

"Yes, Mayuri-sama." she said to him, it assured his heart. Dependable Nemu would always tell the truth, never caring who she hurt really: a spoiled little girl.

He sighed out loud, taking off his hat and wiping away the sweat of his brow. "All this just to tell us that we can't get married. If they had just said this in the beginning, then we wouldn't have wasted so much time. Look at how late it is."

"Yes, Mayuri-sama." she agreed with him.

He stopped and looked into her eyes. They appeared to be shining in the moonlight. "Nemu. Are you crying? Don't tell me that you are, you insensible girl. If you're crying, so help me!" he warned harshly as he waved a long pointed finger in her face, the nail practically threatening to poke one of her eyes out.

"No, I'm not crying, Mayuri-sama." she told him as she shook her head.

He scoffed and looked away from her. "Good. Because this was nothing to cry about. This was just stupid."

Yet, Reader, their knuckles brushed against each other's and for the way home, the backs of their hands remained attached to one another's Reader, he had known that she would be special to him, practically his first-born. He just never suspected that it would become something like this.

Just once, he grabbed her hand outside, and held it close to his side. She came nearer, their shoulders touching. It did not matter what they said, she was still his and secretly, he would admit that his heart was hers.

Even if it made everybody hate him all the more and be sickened by him; he had made her his daughter only to protect her.

So... what did you think?