The concept exploded into the mainstream in 1930 through novel, The Office Wife , and its subsequent film adaptation starring Dorothy Mackaill.
Today, the "office wife" has largely been replaced by the gender-neutral . The Office Wife (1930) - IMDb The Office Wife
The story explores the "human equation" of modern business, where a secretary spends more time with an executive than his actual wife does. The concept exploded into the mainstream in 1930