Welcome, you're very metaphysical -- I look forward to hearing from you!

As for darkness...I don't know. I think the pain isn't really about that at all, just understanding that pain and pleasure aren't opposite sensations at all.

But the fantasies, the control, the humiliation...hard to say it isn't exploring our darker sides, our need to force and be forced, to break from societal norms into the taboo largely because it's forbidden to us.