We are currently inside the manor of the Castellan and because the area around the Castellan is not a neutral area but a hostile area for us three, all of us are capable of harming the NPCs here and we are capable of ending their lives if we wanted to. We can also heal them if we let them get splashed by potions that heal wounds but other than that, they would be suffering from pain and more brutal things can be done to enhance the experience of pain.
Right now, the Castellan is suffering from the wounds that I inflicted on him with the knife I use to harvest materials from monsters. If I use the knife version of my Versatile Weapon, this guy would die before we can get info from him based on the damage that can be inflicted by it alone.