They could either be Attorneys/Lawyers or Soldiers/Agents coming from the very bloodline of the Celestial Dragons. Educated and trained properly for their role.
I think they rapresent the minority of Celestial Dragons that are actually competent at something and in touch with reality (not necessarily good but competent, like the Gorosei).
They are much different from other Celestial Dragons like St. Charloss or St. Roswald and don't waste most of their time on slaves and hedonism, instead they have important roles in the field of Law & Security of the Holy Land.
This gives them jurisdiction in Mary Geoise and they probably never leave the Holy Land.