The professor of smoochology

But when he gets up onstage, Christian redefines himself once again. He's still goofy and flamboyant, but he's managed to regress the audience, to undercut all their knowledge about sex and talk about something so basic that it brings them back to a time before clothes ever came off. He is suddenly the perfect man for this job: unassuming, unintimidating, so simultaneously unpredictable and on-message that it's not just endearing, it's captivating. At one point, he jumps up on the stage and declares that after this show, "You're going to have a lifelong advantage over any partner you're with!" The crowd cheers, and two girls in the front row high-five each other.

During the show, Christian rides what is essentially an hour of nervous energy. The crowd knows these volunteers are unprepared. They can sense it. And when it becomes evident that these students are going to be kissing each other for the benefit of the audience, everyone is enthralled. During the first scene, in which the girls pretend to be barbers by faux-cutting the guys' hair and leaning in seductively, mouths in the audience are literally agape.

Later, people applaud as two volunteers put red pillowcases over their heads to represent tongues, and Christian moves them around to illustrate the three proper French-kiss tongue maneuvers: flicker, rotate and chase back-and-forth. These college students have seen kissing before, but they've, well, never seen it like this. It catches them off-guard, and even Christian's jokes work perfectly. At one point, with the volunteers ready for another smooch, he points to them and says, "When you're this close, don't worry about if you're unattractive. You're out of focus!" The crowd howls.

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"It's just something about my mind that I'm interested in romance," he tells me after the show. "I always wanted to know what my girlfriend was thinking when I was kissing her, and I never found out. So, in response to that desire, I surveyed 100,000 people, and I found out." It turns out, they're thinking a lot of things. They're thinking about how it's too slobbery or there's too much tongue. If they're one of the 8 percent of men that responded to his survey in this way, they're thinking about how good a woman's lipstick tastes.

Christian's interest in kissing was spawned by a 1936 pamphlet called "The Art of Kissing," which he became enamored of because, he says, "It was romantic, it had nice drawings and it was unique." He started passing it around to friends, but soon felt it lacked depth and detail, and so he resolved to fill in the blanks himself. That project led to the book, which led to the presentation, which led to tapes and DVDs and an all-encompassing career.

Now, he says, he gets paid to sleep in nice hotel rooms and make people laugh, and that makes it pretty difficult to regret ever leaving Boston College. At this point, he's even completely immune to the sight of people kissing. "I have a dual feeling about it. You want to give people privacy, but on the other hand, you want to pick up tips, so it's OK." Still, he's hesitant to tell people what he does for a living, and often feels like "a pervert." So, to make himself feel better, he's put into his performance contract that he will, in no way, make lip contact with the student volunteers.

After the show ends, a girl from the crowd approaches Christian and asks why her kissing method influences boys in such a predictable way. When she French-kisses a guy, she says, he wants to sleep with her. When she keeps her mouth closed, he's content to just kiss. Christian tells her that French-kissing often signals an interest in more intimacy. If she can, she should try to talk her kissing partners into a night of nothing more than kissing. He says people often overlook the pleasures of kissing by rushing toward sex, and that unless they consciously take a step back, they'll miss a lot. As he talks, he falls into professor mode, fostering a professor-student discussion on a topic his former career could have never supported. Christian may trade interests and goals at whim, but he is undeniably a sum of his experiences.

The success of his book, he says, means that people always carry some self-doubt about their ability to kiss. I ask him if a detailed book such as his might make the act of kissing too complicated or overwhelming for people, and he says he prefers to think of it as a list of suggestions, not guidelines. There is no right or wrong way to kiss, but there is documentation of what most people like and dislike. He hopes that's helpful.

Christian does 40 shows a year, and spends the rest of his time researching and pursuing new projects. He's stuck with the kissing program for 12 years -- a monumental amount of time, considering his life's short attention span. And even with the Ernest Shackleton shows starting, he expects this is something he'll stick with. Even if he changes his name again, even if he finds a new career, he'll be lip-locked with kissing because it's an inexhaustible topic, he says. People never stop being curious. They want answers, and regardless of what his name is, he'll always have them. "Even if I do retire from this, I'll still get calls," he says. "I could never retire from it. It's caught me up. I could never retire from it. Never."

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