Xaviera Hollander was the biggest madame in the 1970s, eventually being deported after a police raid. What's remarkable about her is how she understands sex and money, love and business, sex with a man and sex with a woman and what roles desire and loneliness play in our lives. 
Talking to her now, in her 80s, she has a breadth of experience and understanding that is pretty remarkable. Her ability to talk, not only frankly, but with her own nuanced point of view, about sex, all the bodily holes and what they can and cannot do, queer identity and a lot more, is fascinating and humbling.