There is nothing abnormal in that happening in the BDSM world. If she is not wishing to participate in that lifestyle she is free to stop. She needs to make it clear that her taste is not what that Master is delivering and she does not wish to continue the relationship. There are groups worldwide in every major metro area devoted to these things. Whether you like it or not, she consented and they delivered. My spouse has been tortured in a friends dungeon before. We have also swung. I have used many a whip and broken many canes over woman happily getting their endorphin rush or orgasm. If you want to save her from the abuse, suggest she fore-go the BDSM and join a reputable swinger site.