I had a professor do this to me. Was an adult going to night school, in my last year. She was about ten years older than me and we hit it off in a way I assumed was a professional student/teacher relationship. Had this with other professors as well.

She told me to meet her at a hotel once, thought she was joking and when I didn’t show was furious. Told her it just seemed odd, and she told me she is getting another one this weekend and not to worry about it, but if I didn’t show there would be consequences.

Through a lot of double speak she let me know if it didn’t happen, there would be no graduation for me. Not knowing what to do, bought a pack of condoms and showed up to the hotel. “No, we aren’t using those”. And that was several of my weekends until graduation. There was zero possibility of saying no, and no one to complain to. I can tell the story online and that’s about it.