Catherine Millet's best-selling "The Sexual Life of Catherine M." was a landmark book a portrait of a sexual life lived without boundaries and without a safety net. Described as "eloquent, graphic and sometimes even poignant" by "Newsweek," and as " perhaps] one of the most erotic books ever written" by "Playboy," it drew international attention for its audacity, and the apparently superhuman sangfroid required of Millet and her partner, Jacques Henric, with whom she had an extremely public and active open relationship. Now, Millet's follow-up answers the first book's implicit question:...