BOOK REVIEW / FICTION : So, What <i> Does </i> the Modern Woman Want? : MIAMI PURITY <i> by Vicki Hendricks</i> , Pantheon Books, $20, 208 pages : TOPPING FROM BELOW <i> by Laura Reese</i> , St. Martin’s Press, $22.95, 364 pages

What does the ‘90s woman want in bed? How are her deepest urges--and the way she expresses them--different from those of women from previous generations? For those who look to fiction for cultural clues, two new novels, “Miami Purity,” by Vicki Hendricks, and “Topping From Below,” by Laura Reese, attempt to take on the modern woman and her appetites.

The first, a slip of a book with sketchy characters and a skinny plot, tells us there’s nothing new under the Florida sun. The message comes via that old-fashioned fictional staple, the good-hearted floozy. Sherri Parlay may be liberated enough to grab sex when she wants it, but in her simple view, it’s still a man’s world, and her major assets are her measurements. However raunchy her behavior, what she wants--and all she wants--is a good man to stand by.

In north Miami, there aren’t many.

“Hank was drunk and he slugged me--it wasn’t the first time--and I picked up the radio and caught him across the forehead with it.” We meet this guy as he expires on Page 1. In quick succession, Sherri’s in and out of jail, bars, cars, the hospital, her bleached hair wild, purse stuffed with schnapps, weary heart full of hope.

She really belongs in an Elmore Leonard novel, in the path of a beat-up cop who needs a reason to believe in God. Her own route to transcendence, after all the booze, scuzzballs and exotic dance clubs, is a day job at a dry cleaner. Honestly. Before long, she’s an expert at getting stains out of anything.

Is it news that a woman can crave sex with the hound-dog hunger of a man? If so, Sherri’s amazing boudoir antics (which I can’t describe here, even though I’m dying to) may seem as up-to-date as cyber art. She and her cleaner-stud boyfriend go at it here, there and everywhere, until it seems like Love at Last.

Well, not so fast, Sherri. In time, the whole thing explodes, revelations come thick and fast, the guy’s actually--big surprise--a bum. The not-so-novel message here: Girls, don’t trust men, don’t get blinded by sex, don’t forgo your independence, even it if means stripping to pay the rent.

In a much more sinister book, Reese draws a similar conclusion. But if “Miami Purity” takes a shallow dip in a turquoise pool, “Topping From Below” drags the depths for bodies.

It’s the story of a woman’s sadomasochistic murder and her sister’s attempt to bring the killer to justice--by becoming sexually involved with the man she suspects. “Michael M.,” an icy music professor, is immediately on to her. Indeed, the sadistic M. relishes the challenge of taming strong-willed Nora Tibbs after the child’s play of subduing her shy, overweight sister.

While denying the murder charge, he freely admits that he abused the consenting Franny. He delights in revealing details to Nora, a journalist, who he rightly senses has a taste for rough sex too. Their affair becomes a game of upping the ante, seeing how much Nora will endure as she becomes, in spite of herself, drawn in by M.

Guilt forms part of her attachment: She wasn’t available to Franny before her death; she can’t quit till the case is closed. But in the face of M.’s sadistic manipulations, Nora’s motives get tangled.

“You’re going to enjoy this, Nora. . . . I promise I won’t give you more than you can handle,” M. tells her, while tempting her with forbidden “disciplines” to come. It’s a game of chicken under the cloak of trust. Are there any limits really? Is he doing exactly what he--and she--wants to do? Who’s to say he won’t kill her?

Reese hasn’t sat with these questions long enough, or thought enough about how to convey this complicated relationship with the right amount of exposition. She gets caught up in Nora’s repetitive--and self-deceptive--hashing of facts (“I want information about Franny, and if I have to sleep with M. to get it, then so be it. . . .”), yet neglects the mystery of how a tough, independent woman becomes a sniveling slave tied to a bed.

There are some horrifying, suspenseful scenes. But the suspense is undercut by endless, beside-the-point reflection in the tone of a journalist lining up facts for a story.

As part of her attempt to explain how people get drawn to S & M sex, Reese employs an involved narrative structure. But sex--especially aberrant sex--doesn’t yield its mysteries easily. A more successful book would have been half as long, full of ellipses and flash-lit sequences that alarmed Nora as much as the reader. Our acts can reveal us as strangers to ourselves. This in itself is terrifying, and enough to sustain a novel.

But back to what modern women want. Toward the end of Reese’s novel, M. tells Nora about one of his students, a pianist, who “understands the music, intellectually, but he doesn’t feel it.” M., who has gotten Nora to move in with him and even told her that he loves her, might be talking about his own emotional vacuity--his mastery of seduction without the solace of true feeling.

This is his tragedy--and Nora’s, and the tragedy that pervades “Miami Purity.” In a culture that rewards personal striving and self-development, we have forgotten how to connect. That’s what modern women are hungry for--and modern men too.