While you were sleeping — or having wild, passionate sex — publishing history was being made. This week a trilogy of “mommy porn” hit the 20 million sales mark in the United States, surpassing records set by both The Da Vinci Code and Harry Potter.

It had never occurred to me to write about handcuffs, millionaires and sex. Nor had any of my writer friends entertained such a muse, though, like me, they’re probably green (or grey) with envy, even as they lament the horrid prose, the cardboard characters and the infantile storyline.

Really, we writers are such snobs. What’s the big deal about literature that transcends time and changes lives, yadda yadda yadda, when you can pen low-brow erotica and laugh all the way to the bank?

The trilogy, which was launched with Fifty Shades of Grey, has owned the top three spots on the bestseller list for more than two months, accounting for one in five adult-fiction physical books sold in the U.S. this spring. It took The Girl with the Dragon Tattoo trilogy more than three years to do what Fifty Shades has done in less than five months.

As suburban moms flocked to bookstores and sex shops, the trilogy was analyzed in Newsweek, discussed on CNN and endorsed by sex therapist Dr. Ruth Westheimer in a YouTube video. Westheimer admits the books won’t win any awards, but says if she were younger and single, she wouldn’t mind spending a night with Christian Grey. He may be emotionally crippled, she says, but the man sure can make love. And he’s rich, too!

No one is surprised that sex sells, kinky sex especially, but I doubt anyone could have predicted this publishing fairytale. Perhaps we underestimate the lure of sex toys or the power of a romantic plot — alpha male saves/sweeps/is redeemed by virginal ingénue. Or how badly we need to escape our ho-hum lives with erotic fantasies.

When author E.L. James came to Miami, two friends who scored tickets to her talk were amazed by the devotion of her fans. Entire book clubs, in matching T-shirts, paid homage, and women talked about how Fifty Shades had reinvigorated their marriages. One man went up to a microphone and said, simply, “Thank you, thank you, thank you.”

I’m not remotely interested in consensual bondage, but you won’t find me disparaging Fifty Shades. In fact, I’m thinking of paying it a compliment.

A half-dozen of us who work out at the same gym have decided to collaborate on our own erotic romance trilogy. The hero will be a geologist and the heroine a therapist, the occupations of two in our group. They will enjoy incredible sex — no shackles, but plenty of gourmet food — while working to save the world in exotic locations. (A perk: The research trips and meals will be tax write-offs.)

We have yet to decided on a title ( Four Seasons in Bed? Drilling for Love?), but we know what we’ll wear to our movie premiere: Studded leather dresses, high-heeled boots and diamond-encrusted reading glasses. Ooh la la.

Follow Ana on Twitter @AnaVeciana.