pronoun. An underground all male sex club located in San Francisco, California; at which, men place their heads into a toilet and allow other men to anonymously penetrate them anally while an audience watches. (Club policy requires all particapants to use latex condoms) A european man known as "Mr. Experience" current holds the club record with 378 penetrations in a single night; he is said to have a DrkXfactr of 378.
Swinging gay men in the San Fran area will commonly ask each other, "what's your DrkXfactr?", or encourage each other to "go Drk(perfom publicly)."