I have two identities: As Mary Bly, I’m a solid member of the intellectual class, a professor of Shakespeare at Fordham University. I wear prim red glasses and tweedy coats and wield my grade book like a weapon. But I’m also Eloisa James, a romance writer whose last 19 novels hit the bestseller list. As Eloisa, I’m nicer, and I wear prettier clothes. (Think pink and, on occasion, sequins.) Having a dual identity is far more than a wardrobe issue, though, because while Mary teaches canonical literature, Eloisa writes its opposite. It should come as no surprise that my two identities sometimes come into conflict.

A case in point: Mary Bly has been invited to speak at the National Book Festival on Sunday — as Eloisa James. This is a little like a soap opera star being invited to present the Gielgud Award. The National Book Festival maps the sacred terrain of literature. My talk will be followed by that of Mario Vargas Llosa, who won the Nobel Prize in . . . literature. Which, by the way, the Swedish Academy awarded him for his “trenchant images of the individual’s resistance, revolt, and defeat.” In case you’re wondering, my novel “When Beauty Tamed the Beast” is free of trenchant images. And, for that matter, of revolt and defeat. Ditto “Desperate Duchesses.” Same for my newest, “The Ugly Duchess.”

I don’t think the word “outclassed” quite covers my feelings.

My publishers were delighted when they discovered that Vargas Llosa’s speech would follow mine; clearly, they had envisioned a sea of empty seats as Washington’s intelligentsia eschewed my genre-fiction credentials. Now that they know I’m the opening act for Mario Vargas Llosa, they’re resting easy.

But I am not. What will people eager to listen to a Nobel Prize winner make of historical romance? What if I’m booed off the hallowed National Mall for having written “trash of the lowest melodramatic order”? What if someone stands up and yells that my lusty heroines match my “intellectually vulgar . . . foolish, offensive, indecent, and exasperating” prose? (Full disclosure: I’m quoting George Bernard Shaw, if only to prove that the righteous battle against “abominably written” trash has been going strong since at least 1896.)

“A Kiss at Midnight” by Eloisa James (Avon)

My father, the poet Robert Bly, won the National Book Award, so he’s been to many a literary festival. “You’ll be fine,” he told me. “Just read them a poem.” Well, I would, except I’m at my most lyrical when it comes to sex. Call me an old-fashioned patriot, but something tells me that reading a sex scene on our National Mall would be indecorous. Desperate for advice, I wrote to my dear friend Donald Hall, the former poet laureate. He wrote back, warning me of a storm of writers demanding to “share” their work. I doubt that will happen. Romance writers shove their manuscripts at editors, not other writers. And writers of literary fiction wouldn’t dream of asking me for advice. I freak them out. Presumably, I inherited some talent; I have a blue-chip Ivy League education. Why on earth aren’t I trying to write the Great American Novel?

One dinner guest a few years ago summed up, unforgettably, what is likely the unspoken conclusion of many: She turned to her daughter and said, “See, dear, you can put all your dirtiest fantasies down on paper and get rich.” All right, then. Never mind the fact that the spectacular success of “Fifty Shades of Grey” suggests that she was prescient: In her opinion, I was lured from the exalted path of literary fiction by the dual pressures of poverty and a libidinous imagination.

The truth is that I do like to be paid for what I write. Even as a child, when putting on performances for my family, I always charged admission. I was already writing romances, because my sister insisted on being a princess, one brother always wanted to be a train, and another was too small to be anything other than Cupid in a sagging diaper. My parents, meanwhile, were training me and my siblings to become great writers. My father read aloud the Anglo-Saxon epic “Beowulf,” howling Grendel’s lines with terrifying emphasis. My mother, the short story writer and essayist Carol Bly, read “Charlotte’s Web,” weeping at Charlotte’s death. We quickly learned the ingredients of great literature: violence, death, grief. It took me years to accept that, though born into the Bach family, I had a pop talent.

Mom never did accept it. Just before she died in 2007, she told me that I would write a real book in five years. My memoir, “Paris in Love,” came out four years and a few months after her death, so I met her deadline. But I suspect she wouldn’t consider it “real” either.

The crucial distinction, I think, has to do with the potential power a book wields. “Catch-22” changed America’s view of war — even though World War II was manifestly a “just” war. My latest novel, “The Ugly Duchess,” will never change a nation’s view of anything. Its triumphs are small, distilled in a note from a woman who wrote to thank me because she realized, again, that “ugly” is a word that exists only to wound, never to describe. There is a place in the world for books like mine, though it’s a different place from those of Joseph Heller. When a reader tells me that she sat by her sister in the hospice, reading aloud from one of my books and laughing together, that’s my Nobel Prize.

These are heady days for romance fiction. I’ve been invited to darken the doors of the august tents of the National Book Festival. And British author Carole Mortimer (“The Wicked Lord Montague,” etc.) was invited to a garden party at Buckingham Palace “in recognition of [her] outstanding service to literature.” My romances may be “intellectually vulgar,” to return to Shaw, but they have their place on bookshelves and — who knows? — perhaps in literary history.

Shaw, after all, was writing about a romance: Shakespeare’s “Cymbeline.”

“The Duke Is Mine” by Eloisa James (Avon)