There was a time when the great American male novelists took delight in writing about sex. Rebelling against a literary tradition that perhaps underestimated how much space animal urges take up in the male brain, many big hitters of the 20th century, like Norman Mailer, Vladimir Nabokov, Henry Miller, Philip Roth, John Updike and Saul Bellow, dived into the muck with the zeal of Rabelais or Cleland.

Sex was freedom, sex was adventure, sex was a good time, sex was pain, sex was life. Masturbation, threesomes, pedophilia, extramarital flings, one-night romps: It was all up for grabs, and how they grabbed it.

In these more tentative times, male literary novelists tend to shy away from such strong stuff. And when these creatures of the workshop do manage to summon up the courage to test their descriptive powers against the most basic of human drives and activities, it is often to chronicle male sexual hesitation, confusion or inadequacy.

Swimming against the current, with a 400-page work of literary devilry called “Undone,” is John Colapinto, a 57-year-old staff writer for The New Yorker who wrote his graduate school thesis on Nabokov and published his first novel in 2001. When his agent, Lisa Bankoff of ICM Partners, began submitting the manuscript for his second novel in 2013, Mr. Colapinto expected several offers. Perhaps there would even be a bidding war. But according to the author, 41 publishers, including every major house in New York, turned it down.