One of the locations in the episode is the Santa Lucia High School. In one shot, the sign is visible, although it's at a not-super-legible angle:
I realized that this was a reference to light, as Lucia comes from lux - the Latin word for light, but then I looked up Santa Lucia and discovered that she's the patron saint of the blind. It's a very subtle reference to the specific characteristics of the Wesen in the episode.
