Someone who is terrible at real life and idles in World of Warcraft for days at a time begging for even the slightest bit of attention from people that he'll never meet in his life. A BDJ is typically fat, disgusting, and completely worthless in every aspect of life itself. A BDJ's only claim to fame will be any sort of "accomplishment" in World of Warcraft that not even his parents could pretend to care about.
Someone with a brain: Yo go target bdj, he just popped a destruction pot to kill that critter and is now actually posting a meter for it
Responder: Good lord what a worthless human being.