So Ciel (or somebody in the Church) has access to some form of memory manipulation... Interesting. She doesn't seem the type to spare the memories of her enemies according to sentimentality, so I suppose Shiki still remembers because he's a nonhuman, or because Arc's hypnosis is protecting him, or whatever the hell's happening with this guy. I doubt Ciel has to do with the original wiped memories that occurred with Akiha and the dead kid in the grove, though. Probably a red herring.