Almight

After killing the spiders in the area, there's a soul I can't interact with and an invisible character there. I know it's there because I can see it's vision radius when I go into stealth. I also can't leave the area, and there's no items to pick up. What's happening here? I can only imagine it to be a bug. I reloaded, did the fight again, same thing. I loaded an earlier save, did the Slayer fight, then did it again, same thing. Insanely frustrating.