The Celestial Race's current Heavenly Emperor, "Sky Art," ascended to the throne over a thousand years ago, but in all those years, the time that the Heavenly Emperor actually spent at the Celestial Court didn't even amount to the surplus of those thousand years.
Before Emperor Sky Art, the Celestial Court functioned as the venue for discussions among the many ministers and the Heavenly Emperor of the Celestial Race, without the presence of a so-called Dean.
However, because Emperor Sky Art has been hands-off since his ascension, delegating his power to the most powerful Celestial at the time, An1, who is now the Dean of the Celestial Court.
The position of Dean of the Celestial Court was also created by Emperor Sky Art for An1.
One might say that within the Celestial Race today, it is An1 who truly acts as the administrator.