Sansa is actually a very powerful woman--she simply lacks physical force, for now. But she withstands the force of a man who is impotent in every other way. It's Ramsay who is powerless and must resort to rape/torture to validate himself. His sense of power is counterfeit. The brutality of that scene, I think, is to set up the reversal of force that will bring Ramsay to his knees. Sometimes implication is better than direct viewing, but GOT is just not that kind of show.

Watch the pilot episode on USA: http://www.usanetwork.com/mrrobot/videos/eps10hell...

Looks very promising.