Since revealing her dark family secret to the public, Mackenzie Phillips has described the period after her father molested her at 18 as "consensual." And although her father was a "damaged guy" as she said on the Today show recently, Phillips also said, "I believe I have some accountability for what went down afterwards."

It's this taboo area that writer Kathryn Harrison explores in her disturbing and beautifully written memoir, The Kiss, about a four-year "affair" she had with her father with whom she reconnected at age 20. With spare and unsensationalistic language, Harrison helps the reader understand how inadequate the word "consent" is when a child is involved sexually with a parent, even when she's reached adulthood. To hear about other insights The Kiss provides, read more.

Harrison's parents divorced when she was a baby, and she was raised by her grandparents after her mother left her at 6 without leaving an address or phone number. Even though they eventually reconnected, Harrison had a strained relationship with her and describes her in the book as narcissistic.

When she was in college, her father, who had become an ordained minister, contacted her, and she, her mother, and father spent a week together at her mother's apartment. It was when Harrison drove him to the airport that he first kissed her in a nonparental way. "In years to come," she writes, "I'll think of the kiss as a kind of transforming sting, like that of a scorpion: a narcotic that spreads from my mouth to my brain." For four years after that, they had a sexual relationship.

Many people may think that Mackenzie Phillips, in "consenting" to sleep with her father as an adult, is as much to blame as her father or that she forfeits her right to our sympathy because she was not a child when this happened to her. By taking us into the mind of a vulnerable young woman, Harrison helps us understand that no matter what age someone is when a parent is inappropriately sexual, that sexual relationship is always embedded in an abuser/victim dynamic. Victims of incest can come to sympathize with and love their abusers — like kidnap victims with Stockholm Syndrome. Like Harrison, Phillips probably took the love her father gave her for a time, no matter in what poisonous form it was given.