Yes! Some disturbing experiments on humans must be happening!
I want the main female villain to be employing some sort of mad doctor conducting experiments with the goal of getting her eternal youth or something like that.
Like, the female villain could be human who wants to live forever and be beautiful but doesn't want to become vampire for whatever reason, and then there are the vampires who are against her because she and her doctor are kidnapping their kind trying to unlock the secret of immortality and youth without having to become a vampire.
So they conduct experiments on both humans and vampires which results in horrible monsters that sometimes escape.
Naturally, the vampires want to take her down, meanwhile the human population is convinced that it is the vampires who are kidnapping their people and mutilating them/turning them into beasts, which they sometimes are when they're hungry but it doesn't really compare to our main villain's current efforts.
So Geralt has the following choices:
- Side with the human villain, help her obtain her eternal youth by committing something horrible (killing someone really innocent for example). In exchange, she will provide you with material rewards, promises to do some politicking like standing up to Nilfgaard, gets her eternal youth and the rival vampire clan that has been terrorizing the humans in that area is defeated.
However, she and her evil doctor now have the means to create an army of vampire-like monsters and that could have terrible consequences.
- Side with the vampire clan, defeat the main human villain and her forces and from here you will end up with some of the following depending on the choices you made:
A) You have failed to obtain any proof that the villain was actually doing all this stuff. The human population of Touissant dont believe you and sees you as someone who conspired with monsters to kill their beloved noblewoman/queen, whatever. The vampire clan is either defeated and Geralt is banished from Touissant or the human forces of Touissant are defeated and the Vampires now rule Touissant under cover.
B) You have proof of the main villain's evil deeds, the humans of Touissant are grateful and will not hurt the vampires if they promise to leave Touissant and not kill any more people when they're hungry. You can either accept that or fight them in which case either the vampires or humans are defeated again.
- Side with the human forces, not the main villain directly but more like some sort of army general who wants to find the truth. Depending on the choices you make, this path can lead you to the conclusion that the main villain is either the human female or the vampire clan. In case you find out it is the female, you defeat her (no option to side with her here) and the humans are happy. They can then either make peace with the vampire clan or fight and defeat them.
In case you are wrong and go after the wrong enemy, the vampires. The main villain then thanks you for protecting Touissant from vampires and rewards you, as Geralt is leaving Touissant, he now finds out the truth but it is too late for everything, you got the worst ending : )