Just some guy so far as we can tell right now... I mean despite the fact he is wearing black, I do not think a goth club is a place he would really fit in. He is there for a reason. Though if that reason is just to freak mark out more, or if he really is some psycho who enjoys hunting geeks, we do not know... My guess is that Joel is somehow behind it though since he is the only one to have interacted with the hunter other than mark. Well, out side of that game, that is...
Not to mention that if he can track them to the goth club, he knows where they left from. And their larp is right where that escape path Joel had set up for Mark lead to... Though personally, I am hoping I am wrong and he really is a murdering psychopath with a sense of humor. They just always make things more interesting.
My name made sense when I first thought it up.
I apologize in advance for the inevitable awkwardness.