University of Chicago A poster promotes the Nov. 1 meeting of RACK, the BDSM club at the University of Chicago. Click the image for the full-size version.

It's a club where you might, in fact, use a club: Harvard University has joined the small but growing roster of U.S. colleges that have approved official student organizations devoted to kinky sex.

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Harvard administrators were to formally approve the group, Harvard College Munch, on Friday, The Harvard Crimson reported. The recognition means the group, which has grown to 30 members since its informal founding earlier this year, can officially meet on campus to discuss issues related to the bondage-discipline, dominant-submission, and sadism-masochism communities, known collectively as BDSM.

More important, its founder told the newspaper, speaking under the pseudonym "Michael," is that the move bestows "the fact of legitimacy."

While Harvard's club drew widespread attention this week, it's far from the only BDSM club officially recognized by, or at least tolerated at, U.S. colleges.

At the University of Minnesota, Kinky U is Student Organization No. 2370. It meets weekly — after office hours "for maximum safety and confidentiality" — to discuss "topics related to kink and the kinky community."

At Tufts University in Medford, Mass., Tufts Kink started meeting this semester.

"I think there’s a number of students who feel sort of isolated and alienated, and I think it's very powerful for them to have just a place where they can express themselves and a place where they can make friends," co-founder Anschel Schaffer-Cohen told The Tufts Daily.

There's no national registry of campus BDSM groups, but consensus is that the oldest is at Columbia University, in New York, where Conversio Virium meets on campus every Monday night at 9.

"Conversio virium" is Latin for "conversion of forces," and the group says it dedicates itself to 'the full exploration of BDSM, both in its sexual and spiritual aspects."

"We encourage acceptance and communication between members," its charter says. "We urge them to learn from each other's play styles and experiences and to set aside any assumptions they may have about who people are and what they do."

Actual sex isn't allowed at such on-campus gatherings, which usually host discussions or the occasional live demonstration of safe and consensual kinky sex.

The point is to "raise general awareness of kink and to promote acceptance and understanding of BDSM," according to the bylaws of Risk-Aware Consensual Kink, or RACK, at the University of Chicago.

RACK is an intellectual group, it says, not a play group. It provides "resources to students who are interested in or curious about BDSM" and demonstrations that "give students an opportunity to learn from experienced members of the BDSM community about safely practicing kink."

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