In the movie Repo! The Genetic Opera, I have a hard time grasping why Shilo would trust Rotti. I know that she's been locked up in her bedroom for years, and he is the only person to have ever even offered her a cure for her illness. At that point, you'd be willing to trust anyone.
That being said, in "Zydrate Anatomy" the lyrics clearly state that Rotti has the right to repossess Mag's eyes, and Amber Sweet openly admits that the Repo Man is coming for Mag.
One would think at that point that trusting Rotti would be off the table for Shilo. Though, she stills disobeys her father and goes to the opera... then, knowing that Rotti is the one responsible for any harm inflicted on Mag (he's in charge of repossessions) she still blames her father when she sees Mag's dead body on stage. She even goes as far as to tell her father that he's been replaced.
"Someone has replaced you! Dad I hate you! Go and die!" I assume she's talking about Rotti replacing Nathan...
I know she didn't actually see Rotti kill Mag, and at that point in the film she knows Nathan is a Repo Man. But, she still knows Rotti is responsible for all repossessions. Even if Nathan had killed Mag, he wouldn't have done it without Rotti's orders. How could Rotti replace Nathan in her eyes? How could she ever have trusted him beyond the point of "Zydrate Anatomy"?