Ghost in a wall
Just a bit spooky
Honestly, after re-reading, I wouldn't be surprised if this "Confirms" that he's a Case 53 that undid the changes to himself. It'd be rather easy to think that All the 'strings' and other things are the bits that are keeping him "human" and breaking down due to March's attack. These interludes are the best though, I'm going to have to reread the story now so that they sink in properly.