Unless and until you have enough of a conversation with someone to truly demonstrate that you aren't asking for absolute power--that you genuinely only want to add more richness to the experience, that any possible risk of power loss is exclusively meant to make the experience better, not worse--a lot of people are going to see, "So, I can mess with your character at any time, for any reason, and you just have to live with it, right?"
Trust is not automatic. It is earned. Asking up-front for "I get to treat everything you love about playing your character as my personal chew toy", even if you would never actually do that, is a really, really, really big ask.