Cat People (1982)

The 1982 remake of Cat People has a very nice scene near the end of the film with Nastassja Kinski.

She's part of a race of shape-shifters--people who change into panthers--who wants to end it all by remaining a panther forever. To do this, she must have sex.

And in order to do THAT she must first be tied down to the bed in a spread-eagle position.

So although she's tied down to the bed, it's still completely consenual. It's interesting that all of the movie leads up to this climatic (in every way) scene.

It includes full frontal nudity (of Kinski), which I can't show here, but you can see everything on the Blu-Ray/DVD/un-cut streaming copy.

If you want to seek out the original Cat People, thinking it might also have a bondage scene, don't bother. Only the '82 remake has this nice moment.