When “Fifty Shades Freed” opens in theaters on February 9, fans will no doubt flock to see bad boy Christian Grey (played by Jamie Dornan) bested by naughty-but-nice heroine Anastasia Steele (Dakota Johnson).

A less racy but equally thrilling story, my research shows, is how romance writers are getting ahead in the digital era.

While economists and labor scholars wring their hands over the rise of the precarious gig economy, these freelancers have developed innovative business practices over the p…