I love the fact that she is evil but not absolute evil and she has a deep personal drama in her backstory. Most likely, she can be really good with us if she will trust and respect us over time, and we will show that we will not betray her for profit as is customary in drow Lolth society
This as far from truth as it can be. She is psychotic sociopath that fits a serial killer profile. She kills for pleasure and without any reason. If you don't think this is absolute evil then I don't know what to say. There is no drama in her backstory, she's a typical drow, who is paranoid to be backstabbed. Characters with no empathy just cannot learn to trust and respect anyone because it's like for a blind person to learn to figure out colors. Sociopaths can never be friends (they can pretend though), they just cannot feel friendship on a biological level due to lack of empathy. If you want believable behavior, the only way for her to behave respectfully is if you will gain a total and overwhelming control over her, if you can end her life at any moment and know her intentions at any time (using tadpole). Then she'll obey due to fear, switch to boot licking behavior and backstab you if she'll find reasonable opportunity.
Don't get me wrong, I'm all in for adding evil choices and fun evil roleplaying but I want it to be well made and believable.
