It took me many years to figure out that I wasn't who I was pretending to be. Outwardly, I'd become a bold, brazen adventuress who made a habit of propositioning men she hardly knew. I'd hand my phone number to a guy at a party, arrange to meet him on his doorstep, spend an hour or two in his apartment, and slip away. Every time I did this, I felt a curious combination of victory and devastation. I was afraid of something that I couldn't pinpoint, and I wasn't nearly as frisky and footloose as I acted. I was a confused young woman who had trouble trusting men. Easy sex was a tactic to keep men at arm's length by treating them as conquests. If this sounds like something a guy might do, it was. Alarmed by the power imbalance between men and women, I thought sleeping around would even up the score. I wore my sexuality like a protective suit of armor. My swaggering bravado was a put-on. I led a rather sad, disconnected life—until I mustered up the courage to let my guard down. I can't help wondering now if maybe there are some women out there, like me, putting on this same kind of act, suppressing their passion and vulnerability. I believe women today are under pressure to reinvent them, to conform to a bed-hopping, no-strings ethos that's in vogue.

Now that the love affair has been replaced by the booty call, it's fashionable to treat sex as something without weight or meaning. Our aggressively modern culture has chipped away at our collective faith in romance. Decades ago, The Joy of Sex made history with its illustrated, step-by-step recipes for lovemaking. It was a useful, practical source of information, except for one colossal error. Unlike cooking, sex isn't a hobby. People aren't playthings. They're richly intricate creatures full of good and evil impulses, psychological conflicts and contradictions. Sometimes we insist upon a "casual relationship" to deny the uncomfortable truth: Sex is complicated.

As a society, we've tried to simplify things by separating physical pleasure from emotional attachment. At the same time, we've started to confuse sexiness with physical perfection. While we're running off to our plastic surgeons for Botox injections and breast implants, we've forgotten that what's really sexy can't be bottled. It's an inner spark that's as distinctive as your personality. Being hot is a state of mind, and it's subjective. It takes two to generate heat. Desire demands emotion.

In fact, the alchemy of attraction is so personal and inexplicable, no one fully understands it. Poets, playwrights, and novelists have spent centuries trying to grasp it. A how-to guide can teach you how to have a bigger, better orgasm. A vial of Viagra can "enhance performance" so you can sex around the clock. But there's no secret formula for what floats your boat, or who. Ever since I stopped leaving my heart on the bedside table, I've thought of sex as mystical. Romantics like me may be an endangered species, but instead of trying to blend in at the swingers' parties, let's stand up and be counted.

Lisa Dierbeck is the author of The Autobiography of Jenny X(Picador).

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