If Evie was going to threaten him, he would not see it coming. That she stood in front of him was a clear indication that she was not out to hurt him.
"It's much easier to have an enemy take out his friends than kill them all yourself. If one man will kill two or three of his allies before he dies himself then I can focus on the real target," she explained with a small secret smile.
She thought most people were aware of what she was, an Assassin. These people were her allies and so she trusted them with the general knowledge that she killed bad people to protect the world. If he wasn't aware of that then he was learning very quickly. "I'm happy to test any formula you develop. I'm sure there will be a threat soon enough that can provide volunteers. Oh, that one you're holding?"
She gestured with a flick of her fingers, "Does not work on the undead. Something that does would be nice, whether it is the same formula or a different one I am not particular. I can find ways to carry more vials."