I will acknowledge I have seen this, but more common is a slave and a moderate switch submissive - where the sub will go along with a lot - but not being tortured - at least not that severely. It appears to me, the one being kicked acts very much owned, not sure about the other. The reality at the end of the blind dragging her around and easy ordering suggest a sense of absolute certainty that her actions will be met with obedience and acceptance.
not sure the girl doing the kicking would have been happy to go along. The girl getting kicked - well seems like she doesn't care to be anything but owned.