Neither.
It is my own version of World of Darkness rules. See the World of Darkness Core Rules doc that is provided along with the Demon rules.
I am afraid I do not have a bestiary or antagonist book, that is still in progress at this time.
In the demon rules, however, there are some rules I started for generating Seraphim and Sorcerers which are the primary antagonists to the Demons. You can use the base mortal World of Darkness rules to make those as antagonists.