This did appear in a thread a few months ago. There is, indeed, another shadow that appears where a third character would be standing. I believe the general consensus was that a character was supossed to be standing there, but they took it out later on the game.
In fact, now that I think about it, it might have to do with the fact that Grobyc stands in that spot, but either bad programming or a minor bug prevented the circle from disappearing when he's no longer there.
