It might be fundamentally impossible to have a god as a ghost, but maybe someone from the royal line? Like a dead queen or prince perhaps
Oooh I wonder if something’s gonna happen to the current crown prince will turn into a ghost and she brings him back…
We already seen 100s of dead princes
But they’re all zombies ghosts that she can’t talk to. There isn’t one that she can just yet as she doesn’t spend even time in the imperial palace.
We started of with basic ghosts like the butler and chef then we got the spirit of the founding sword and now a saintess…what’s next a goddess?