Guess what! Hookups are not just for college students. In other news: Young people didn't invent sex. You wouldn’t know any of that from the media coverage of casual sex, which invariably focuses on the carnal aerobics of hot young keg-standing coeds. Nor could you tell it from scientific papers on the topic, which, like so much research, rely on collegiate samples. Zhana Vrangalova, herself a sex researcher, is changing that perception with the Casual Sex Project, a website that solicits true hookup stories from people of all ages and from around the world.

These flings are not set in dorm rooms, frat houses or university libraries. Among the responses Vrangalova has collected thus far, there's a threesome outdoors in the countryside, impromptu sex next to a headless stuffed sheep, a tryst at a swinger’s club in Manhattan and a “happy ending” at a massage parlor. There are also more prosaic flings in bed and, of course, in the back of a car. There is awful sex, glorious multiple orgasming, and one experience that sounds like sexual assault (and yet the woman writes that “it was so hot”). Sex is had sober, drunk, stoned and high on coke. There is BDSM, infidelity and bittersweet ex-sex ("He felt his way around my body, and I let my hands remember all that they once loved to hold").

Some descriptions are erotic: "Rubbing my neck, holding my hand, slipping his fingers in and out of the sleeves and neckline of my shirt. Dipping a few times into the edges of my bra." Some are schoolgirl gushy: "He grabbed me and kissed me and my head exploded. BEST. KISS. EVER." And of course, this being sex, there is plenty of humor, too: “I’m panting and looking at her smiling while she out of nowhere grabs some moisture off her vagina and brings it up and anoints it across my forehead while saying ‘siiimmmba,’” writes one man. (The "Lion King" reference was apropos of nothing, making i...

In your scientific research on hookups, what have you found about hookup culture's emotional impact?