The Building was gigantic in size, it resembled a mix between a middle ages castle and the main tower of a battleship. Its was heavily stocked with missiles and technical equipment. The two side towers are held up by gigantic statues of a man and a woman being crushed.
The Anti Demon Corps HQ was a heavily armored building built upon an old weapons factory that was missed by the demons attacks on humanity's weapon supply. It was the main hub for humanity's Demon Busters as well as many various rooms such as science labs, living quarters and various torture rooms. As a mainstay of defense there was a large Brain Waves Detector located inside the building that would be able to detect anyone non human trying to approach the building. The parents of Kensaku and Miki were horribly tortured at the building after they helped Akira Fudo escape the Demon Busters.
When Akira is told of this by Dosu-Roku he gathers a massive army of Devilmen to help him in his attack on the Anti-Demon Corps HQ. The sheer number overloads the Brain Waves Detector, Demon Busters are sent to deal with the threat but are blown back and killed by their immense force. They succeed in killing a few Devilmen, however the building finally falls ending the Demon Busters once and for all.