The workshop (工房 kōbō) is a personal laboratory of Nine that is situated between the Boundary and the Kiln of the First Area.
After the Great Dark War, she worked here on the 11th Arch-Enemy Event Weapon, the Corpse Burial: Requiem, intending to replace the Master Unit with it.
In order to seal the workshop away, Kokonoe Mercury placed the 7th Agency facility directly on top of it.