Pathfinder: Wrath of the Righteous often offers more than one outcome to a situation and if you are wondering about the ones in Camellia's companion quest, here is the answer.
Owlcat Games put many intrigues into the story of Pathfinder: Wrath of the Righteous , some of which you will miss, depending on your choices. A Noble Intention is one such occurrence and considering this is story content, we would advise you not to read further if you haven't reached this point yet, in order to avoid spoilers.
If you completed the quest, however, you are likely to wonder "What if?".
Well, after discovering the horrible truth of Camellia's extracurricular activities, she presents the Knight-Commander with a seemingly impossible choice - either let her keep doing it, kill her or spare her under the condition she ceases with heinous acts.
Killing the serial killer is the choice countless players will make and if you are wondering whether her ritual would work, well, there is no ritual, to begin with. Camellia's amulet doesn't contain a spirit. It was a lie made up to throw you off her scent and she is merely a deranged serial killer.
There are a few telltale signs in the story that can lead you to this conclusion. If you went for the Azata Mythic Path, you saw her dark desires in the dream sequence.
Upon facing her in the basement, you can let her try to explain herself but you will notice she enjoys her depravations and if you get her to mess with her amulet, her alignment will no longer be obfuscated. You can inspect her at that point and you will see that she is Chaotic Evil.