OH I LOVE THIS ONE !!

Low
“What do you need ?”

Medium
“Something on your mind ?”

High
“Always a pleasure to see you, friend”

Lover :
“Welcome back, warmth of my day”
"Light of my night, you're here"

Eole's good route would lead to her setting free from her dark urges and she can finally start living her own life. If you're romancing her, her own life would be by your side and she'd like to build a family with you and be surrounded by the people she loves. She finally finds peace in a home she never had !

Eole's bad route is if you associate her worth with her dark urges. She automatically leans toward letting go of her bhaalspawn legacy if you don't intervene a lot in her storyline, but with enough successful rolls, you can convince her to embrace her legacy and urges.
Considering you decided to defeat the netherbrain and after succeeding, she'd try to kill you because she has realized you've manipulated her. Roll for initiative! If you manage to kill her, that's it. She is dead. If she managed to kill you, she'll then go back on the road, wandering without purpose.
If you have romanced her, you can try to avoid the fight by rolling for deception or persuasion to manipulate her feelings further, saying things like "you don't want to do this, think about everything we went through together" "I love you don't do this" etc, which leads to her leaving you and the party forever and, again, she ends up wandering without purpose.

THANKS FOR THE QUESTION IT WAS SO FUN TO THINK ABOUT IT !!!!!