During the years of Apartheid. when two people of different races did mix both felt ill at ease, even embarrassed.
It would remain to be so even after Nelson Mandela's release from Robben Island prison.
Blasphemy, pornography and endangering the security of the State were all reasons for South African censors to ban books. By the 1970s as many as 20,000 books had been banned.
A line in a book like “Oh God I’m tired!” was considered blasphemy. Even a four-letter word might be considered pornographic.
A simple joke about the South African police might be seen as endangering the security of the State.