++Perhaps the Death Busters could be an organization founded on some sort of human trafficking? Not necessarily trafficking as in prostitution, but trafficking as in preying on and recruiting “broken” women (ei the Witches 5) by taking advantage of their vulnerabilities, “comforting” them, and providing them with some sort of benefits “...to achieve the consent of a person—in this case, Kaolinite (and/or Tomoe perhaps?)—having control over [them], for the purpose of exploitation.” (Definition: https://www.unodc.org/ ) However, these benefits could come with a catch, perhaps even a threat(?) that would drive the women to obey. For example with Cyprine, Kaolinite (or whoever) could easily manipulate her by coming up with something along the lines of “I can bring your sister back to life, but in order for me to do that, you must first [blahblah...] If you fail to do this, you will live the rest of your life [blahblah...]” Heck, maybe the “taioron crystal” drug (see explanation below) could be the Witches' false sense of benefit that ultimately ties them down to the criminal organization due to its addictive properties and the way it tricks them into believing they are helping themselves overcome their biggest personal struggle(?) fear(?) sense of insecurity(?). They wouldn't even realize they were being exploited. As far as how they are exploited, I am not entirely sure. Perhaps the Witches are recruited with instructions/encouragement to commit a series of specific crimes? Maybe they operate a drug ring? Or are part of the black market trade?

++Do you think the hierarchy among the Witches should be the same? How should it be determined? By number of crimes they successfully commit or by how loyal they are? Cyprine obviously wouldn't need to commit 999 crimes LOL. I'm already assuming that witch levels are out of this unless you guys really want to keep them in. XD

++Regarding Kaolinite as a character (NPC or RPC), I could see her as the lure for the Death Busters (if not the mastermind behind the whole recruitment thing). She could have an eye for vulnerable women, who she would frequently search the city for, using deceptive and manipulative methods along with empathy to gain her victims' trust before offering them help (ei exploiting them XD). Perhaps she tried to recruit Ptilol in the past with one of her mind games?

++Ptilol's death: I'm still not entirely sure what would make Ptilol want to kill herself, so if anybody has some ideas, please do tell! All I can think of right now is that maybe Ptilol has a strange fear of becoming Cyprine's literal clone. Perhaps she gets compared too much to her sister in an annoying/negative way—or perhaps even receives less recognition for her work when the two of them are evenly matched/skilled. Maybe Kaolinite saw this in her and tried to take advantage of it one day, coming into their shop to have a dress made? (assuming the twins are seamstresses/tailors) but her words were too much for the girl(?) and were what convinced her to believe that she shouldn't even exist.

++Tomoe and his assistant Kaolinite get banned from academic society for misuse of the laboratory for their own gains? Or maybe they lied about their findings (perhaps even to cover up the fact that they were running illegal tests)? That would be the easiest, most realistic way to get kicked out of academia. Somebody checks the data and discovers inconsistencies or something. After they get kicked out, perhaps they move onto experimenting on people? After all they don't care about the well-being of others as long as they are able to ahead in life. (Need more ideassss)

++“Taioron crystal” could be the street name for the drug that they developed and are distributing to their recruits as an incentive. For some reason when I think of "Death Buster" as a phrase without context, it makes me think of somebody who attempts to transcend the mind and body / life and death toward some sort of bizarre spiritual enlightenment. What if the drug is said to be a source of life and power to those who end up taking it (I know this isn't supposed to parallel canon, but Easter eggs are kinda fun, right? XD) because the crystal gives them this false "I'm invincible! Nothing can stop me now!" sort of motivation coupled with a specific side-effect that varies from witch to witch and psychologically enhances their experience without actually increasing their power or giving them a superpower. Perhaps the side-effect could be based on the one thing in their lives that makes them most insecure or upset? (So in Cyprine's case, that would be the loss of her twin sister Ptilol.) To give themselves more confidence (or to stabilize their nerves), the witches could use the drug before committing crimes and/or entering battle.

++The drug's side-effect on Cyprine: I was thinking that it would cause her mind to see the doll as a real person leaving her arms to help her out in battle, when in actuality the doll never leaves her arms or talks. However, knowing that she has a “partner” would boost her self-confidence in battle and make her a much more formidable foe, even if it's actually just her talking herself through the fight in Ptilol's voice. XD

(Could not resist lab coat variant.)