Marian Alston derides loyal slaves as "House niggers..." (On The Oceans Of Eternity, p. 548)
I find that I have twice quoted a black colleague who identified himself as a "field nigger." (See here) The first time was in connection with Sandra Miesel's humorous Afterword to Anderson's and Dickson's Hoka series, the second in connection with SM Stirling's Draka series, and now we are reading Stirling's Nantucket Trilogy. What different works! Yet serious points about real societies emerge even from fabulous or humorous fiction.