Can the word penis appear in a romance novel, or is ”the throbbing evidence of his male arousal” still the euphemism of choice? Back in the mid-’80s, when I was still Tory Cates, author of what the industry calls ”contemporary category romances,” I knew the answer to that and most other questions of romance-writing etiquette. But the rules change quickly and a writer must pay attention, because contemporary romances — not the historical bodice-rippers with their period-costume covers — are the heart and wallet of a multimillion-dollar business.

A contemporary category has an up-to-the-minute setting with heroes and heroines to match. Most are published by Harlequin or Silhouette, both owned by the Torstar publishing conglomerate. Some 600,000 readers belong to Harlequin’s book club and buy, sight unseen, month in, month out, every book in their favorite series. Readers’ letters, focus groups, surveys, and sales enable the editors to keep their fingers on the pulse of their audience. This information in turn is passed along to writers as guidelines. Looking at these tip sheets after being absent for more than five years, I’m convinced that if you want to know what is up with women in the land, you could do worse than consult the rules of the romance-writing game.

The plot must force the couple together, yet prevent them from surrendering to their desires too early in the story. Otherwise, some new elements have been introduced of late. Time travel and the paranormal are now staples, with heroes from the future and ghosts from the past raising heart rates just as flesh-and-blood heroes do. But ”today’s brainstorm becomes tomorrow’s platitude,” warns Marsha Zinberg, senior editor of Harlequin’s Superromance series. She offers a list of overused devices to avoid: developer at odds with environmentalist; amnesia; the renovation of old inns; and heroine afraid of giving up ”hard-won” independence.