For reasons that have yet to be patched, Resident Evil: Operation Raccoon City sometimes results in this glitch you see above. If you search YouTube, you'll find a couple of video entries where players find themselves inexplicably duplicated. The extra character mirrors your every move, which seems to confuse both the player and the zombie enemies.
As much as I love horror games, I'm still a bit of a pansy when it comes to playing them at long lengths of time. Having the extra company with me doesn't seem like that bad of a deal.