It is amazing how some people think that, just because they are in a "BDSM" relationship, they suddenly become either master of all they survey or they must follow every single command they are given with complete blindness.
I counselled a young lady a few months ago that had been a submissive for about three weeks. She started a relationship with a man she'd met online in her area. On their first meeting, before any negotiations were made, he stripped her completely nude, put a leather collar on her which he told her she could never remove, made her get on her knees and perform oral sex on him, and then he bent her over a table and sodomized her.
She told me it was the most painful and degrading thing that had ever happened to her and she wondered how submissives could live like that and enjoy it. When I asked her why she thought all submissives lived like that, she told me that her partner had told her that's how it was.
That was one long session, I don't need to tell you.