Greg Araki may not have been solely responsible for the “New Queer Cinema” movement of the 1990s, but he certainly gave it an edge. Now, he’s back to the big screen with “I Want Your Sex,” a new erotic comedy-thriller that proves he hasn’t lost that edge. In today’s world of “purity politics,” that might actually be the most transgressive thing of all about Araki’s film. In any case, “I Want Your Sex” doesn’t make judgments about any of it, just observations – with wit, slyness, and a refreshingly sex-positive attitude. Shrewd, sexy, and all in good fun, it might well be the most fun you’ll have at the movies this summer.