You've mentioned that Contor specifically is actually decently kind compared to the other demons. Has it ever gone so far that Contor has actually gotten along with one of her vessels? Did any of them like being her vessel?
funny you should ask that actually because Contor has to employ a specific method to find new vessels. since her act is contortion, she needs a body that can perform extremely flexible feats, so she can’t just grab any random person off the street— she has to specifically scope out a victim and get them to come to the carnival. she did this exact thing with Charlotte: she joined Charlotte’s acrobatics club under the guise of wanting to become a contortionist (which Charlotte also was), befriended her, then made up a story about how she was hired by a circus and invited Charlotte to come watch her performance. Charlotte took a few of her college friends to the show, but she was the only one who survived. her feelings on Contor are extremely negative as a result.
Contor feels really bad about having to go through an entire charade with her vessels instead of being able to just grab one and run, but she knows she has to do it to keep her spot in the show. she grapples with her own morality a lot, but let’s be real— she’s right where she wants to be with the things she needs. she could leave if she wanted, but, well, why would she?
(to loop back around and actually answer your question, yes she’s befriended vessels before but none of them have enjoyed being her vessel)