It's a part of the night sky that's completely void of stars. Just an infinite abyss that gets ever darker the longer you look. And the longer you look, the more you hear.
Madness string 85952
When the Menji government banned Samurai from openly carrying swords, many resorted to concealed blades disguised as bamboo poles, wooden walking sticks, and human spinal columns, all of which could be carried in public without causing suspicion.