In reference to this post I made about a couple of weeks ago, I'd like to go further into depth of how Hikaru's Crux was studied. In this headcanon, please be mindful of the following content warnings: child abuse, torture in a medical setting, and the ethics surrounding human experimentation in the name of "science."
When Hikaru was born and her Crux was discovered, scientists were intrigued on how this particular human could have developed another organ in the womb when her own mother, Katsumi, didn't have one. During Katsumi's entire pregnancy, the additional organ was discovered during routine ultrasounds, but there were discussions into the ethics of testing on an unborn fetus that could lead to Katsumi possibly miscarrying. Not just that, but Tamotsu, Hikaru's father, objected to the point of practically almost getting arrested for threatening to hurt the scientists that wanted to experiment on his wife and unborn daughter.
So, they held off until Hikaru was born so as to carry out their experiments when the Crux was fully developed.
This wasn't met without a great deal of resistance from not just Katsumi, but Hikaru's father, Tamotsu. The both of them vehemently argued to not test their daughter at all, thinking that she deserved so much more than being nothing more than something to gawk at because of being born with something else that no one else, at the time, possessed. For at least five years, Hikaru was able to grow up in a happy family until she was voluntarily given up to participate in the PIPE's training program in an attempt to turn the tides of war. They only gave her up on the promise that no experiments would be carried out on her because of her Crux.
The PIPE, desperate to continue living instead of losing the war against the Gnocem, promised they did. However, promises can be broken and it's one of the PIPE's horrible secrets that they've kept under lock and key this entire time.
See, after Hikaru had been given up by her parents, things were okay for a time. She was properly cared for, treated with respect, and told that things were going to be okay. That was, until, the same scientists who were intrigued when she was still in her mother's womb arrived and brokered a deal with the PIPE: they can test on her all they wanted if it'd produced the results they were looking for and that was to be humanity's weapon in the fight against the Gnocem. The deal was agreed upon and this is where things had taken a turn for the worst for Hikaru, who still was a child at this point.
At first, the experimentation wasn't that bad. Just a few shots and blood tests, really. But when that didn't reveal anything regarding the capabilities of Hikaru's Crux, they had to get "creative" with their testing and by being "creative", they resorted to procedures where sights like these [CW: needles in image] were unfortunately common practice with Hikaru strapped to a cold, metal surgical table and pleading for them to stop hurting her and that she was sorry for whatever she did to deserve this punishment.
Sadly, her pleas fell on deaf ears because it went so much further than just injecting her with multiple drugs. They wanted to see how she'd be able to heal and how much pain she could withstand. So, they went through with not just stabbing and lacerating her, but full on maiming by shooting her through her hands and feet. Again, her cries for mercy went ignored. However, these extreme methods of testing her endurance and pain tolerance finally paid off during her training regimen that she was still expected to go through. They ultimately made her stronger, and in their eyes fortunately able to withstand much more in terms of increased training.
Yet, no one thought about how she was still just a child. During these experiments and training, they slowly whittled away the bright and happy girl that started on this because she was promised that she was gonna be a hero and save the day! How could a child resist that? The PIPE and the scientists kept on saying that this was all in the name of making her a hero, like they promised she'd be.
Was being a hero worth all this pain and misery, though? That was one of Hikaru's many thoughts while she was in her room, quietly sobbing into her pillow at night until she finally was able to sleep, having passed out from the pain and discomfort she was in. Hikaru also learned that no matter how many times she cried or apologized, they'd still carry out the experiments on her, so eventually she'd just lie there and take it, trying to not make a single noise for fear that it'd only ramp up the experiments' intensity on her.
And the way that she was rewarded for this? They simply gave her treats, which were one of her only comforts. She couldn't contact her parents to tell them what was going on and the reports that they received told them that Hikaru was being well taken care of and was happy. Nothing was wrong in their eyes, even as they kept on forgetting the most important aspect of this whole matter: Hikaru was still a child. Yet, if it produced results such as giving them little victories here and there on the war, so be it — they would continue this extreme training regimen and keep on lying to her parents that she was being treated the way that they had promised. To this day, they still don't know what sort of hell their own daughter has been through and Hikaru doesn't want to upset them by telling them the truth, either, because of how these experiments gave them the stability that they have today.
As Hikaru grew up and became more powerful (along with being broken down and molded back into what the PIPE wanted of her), the experiments eventually ceased altogether, but this gave her a lasting fear of anything medical because of the hell she was put through. As previously mentioned, Hikaru is very critical of others tending to her injuries that she sustains in fights since she'd rather be the one to patch herself up because she doesn't trust anyone else to do it. Those in the medbay only admonish her for getting hurt for the umpteenth time and don't have any sympathy for her, no matter how grievous the injury really is. So, she'll often be by herself, dressing her own wounds while trying to stifle her sounds of discomfort however possible. This behavior of hers is still prevalent to this day because of how deep seated her own fear of anything medical is concerned — all because the PIPE saw her as nothing more than a weapon instead of a human being.
As far as anyone's concerned, the PIPE is heralded as this pillar of strength and hope, but no one publicly knows just what it took to get there. It's still classified information that only those who are higher up the food chain are privy to and have sworn to never reveal to the public the atrocities they committed to attain the semblance of peace that they have today. Anyone who tries to speak up about the human rights abuses they committed is silenced, never to be seen nor heard from again.
To Watanabe and others, the PIPE is nothing more than a shining beacon of peace and prosperity in the world and nothing shall ever taint that pristine image that they've cultivated for themselves all these years.
