Gabe I love all those little twists COB put in their songs, transforming them from simple good tunes into subtly (or not so subtly) creepy ones.
This one has piano tinkling in the background of the chorus. Very old-sounding, almost ghostly, quite like a faded black-and-white photograph actually. It creates a very interesting effect with the foreground because you can hear two distinct musical 'planes' transposed over each other. Clever clever wonderful job.