I'm writing a story in which a woman is holding a man prisoner in her house, and I want her to confine him whilst she leaves the house for a long period - 12 to 15 hours is what I have in mind, though that's flexible.

I have been mulling over having her put him into some sort of bondage, but this is an area I don't know a lot about. I've only depicted it once in a story, and got an email pointing out that as described, the guy would probably have died within a few minutes!

I gather that in real life it's very inadvisable to put somebody in bondage and leave them unsupervised. In the story the woman isn't particularly bothered about the man's health as such (it's a very non-consensual situation with a very sadistic woman), but she also wouldn't want to get back and find a dead body on her hands, given her long term plans for doing various nasty things to the guy.

So my questions are

How practical is this scenario? Is there some way of tying people up so that it is safe to leave them alone for extended periods? As much detail as possible of safe equipment and methods, if they exist, would be appreciated.

Can this be done in such a way that the man is in physical discomfort, but not danger?

If this is just an impossible scenario I could simply have her imprison the guy in a room or something, but that lacks a certain appeal!

Grateful in advance for any advice those experienced in this sort of thing can offer...