These are the officially licensed World of Warcraft robes available from ThinkGeek. They cost $130 - $150 apiece and come in Draenei, Malefic, Bloodfang Rogue, Paladin and Priest varieties. Obviously, they're for having sex in while pretending you're a World of Warcraft character. And there is absolutely nothing wrong with that. You are going to need some accessories though. I suggest at least a magical staff or some sort of love amulet. God, I remember the first time I role-played with a girlfriend. "What did you role-play as?" Well she was herself, but she wanted me to pretend to be her ex-boyfriend.
Keep going for more shots including what several of them look like on real people.
Thanks to Slysyv, who agrees role-playing is key to a healthy sex life after you get tired of one another for who you really are.