Ex-Girlfriend Reveals John F. Kennedy Jr.'s Wild Side

March 4, 2011 — -- Almost 12 years after his untimely death, one of John F. Kennedy Jr.'s ex-girlfriends reveals a side of the former first son few people knew.

Christina Haag, the woman JFK Jr. dated for five years during the latter 1980s, chronicles her relationship with him in her upcoming memoir, "Come to the Edge." The two met as teenagers growing up in Manhattan and became friends at Brown University, where they bonded over their shared love of acting. They started dating post-graduation after they were cast in the same New York play.

The April issue of Vanity Fair includes an excerpt from Haag's book about a trip to Jamaica that almost ended with the couple drowning in the Carribean. Below, seven of the most telling revelations from that excerpt:

As a teenager, Kennedy and his friends hurled paper towels stuffed with Noxzema out the window of his mother's 15th story Fifth Avenue apartment: "He darted back and forth, cracking himself up. Skinny, with hair in his face, he seemed younger than the rest. And he was really into throwing those Noxzema bombs. 'Nice one, Kennedy!' they'd yell."

He liked nicknames: "He called me Chief, and I called him King."

He was curious about tantric sex: Haag writes that for the vacation, Kennedy packed "a book on tantric sex a friend from Andover had given him after returning from Thailand. 'It comes highly recommended, he said with a wink.'"

He smoked marijuana: Offered a joint by Jamaican locals, Kennedy, writes Haas, "stretched out on the sand and finished what was left of the joint."

He called out to his mother in times of need: After Kennedy steered their kayak into a boulder off the coast, Haag writes, "I saw John, my captain: John, who was never afraid. Unable to be still, he paced the beach muttering something, his eyes wide and to the ground. 'Don't tell Mummy, don't tell Mummy,' he repeated like a mantra to no one. Mummy wasn't there, and he wasn't talking to me. I could have passed my hand in front of his eyes and he would not have blinked. It was then that the danger we had been in really hit me. John was afraid."

He couldn't stand to see suffering: After breaking her foot while horseback riding, Haag writes, "John would gallantly carry me up the five flights of stairs to his brownstone apartment, but he wasn't able to look at my cadaver-like foot. Nor could he bear to hear how painful it was or of the fears I had. He wanted me to be a trooper, a sport, but for all his exploits, he was squeamish about blood and weakness of any kind."

His sense of adventure knew no bounds: Haag writes that after their near-death experience at sea, "When we pulled into Great Pedro Bay an hour later, I was still shaken. John seemed fine, oblivious. As he pulled the kayak past the fishing skiffs to a fence near some old bikes, he whistled. Unlike me, he had left it all behind and was fully in the present -- although he did make me promise not to tell his mother. 'But, John, we could have died.' ...'Yeah, Chief, but what a way to go.'"