There is a false binary embedded in mainstream culture: that “vanilla” sex is inherently ethical, and BDSM is morally suspect. But ethical sex has never been about style. It is about intention, awareness, and presence.
A performative “yes” given in a moment of emotional pressure is not ethical, even if no rope touches the body. And a submissive begging to be used, within negotiated bounds, is not unethical, even if she kneels with her mouth open and tears down her cheeks. Pre