What I learned working in a porn store: It starts with the way they open the door. Some press their faces against the outside glass of our large storefront window and pretend to look at the mundane Hollywood films while surreptitiously angling their eyes to the room marked "Adult XXX." Some try to sneak in, shoulders down and head to the side. My station is right next to the entrance and, knowing they've been caught, they reel around and greet me with a laugh not unlike a hyena. Some burst in, yelling their demands before the door has even banged into the opposite wall. A constant trickle of men in their mid- to late 30s, heterosexual, varied ethnic and economic demographics bound by one thing -- pornography. Whatever their way of announcing themselves in this Philadelphia sex shop, two things are certain: