THE NAUGHTY WORLD of W.M. Spackman is located somewhere between a scoop of Evelyn Waugh and a very un-McCarthy-like Gropes of Academe. In A Little Decorum, For Once the witty exchanges between lovers are caresses, avenues of sensuality, while the sexual skirmishes are farcical, irrevelant. Set on and off the Princeton campus, A Little Decorum, For Once is a whirly, madcap battle of the sexes, updating those light, frothy turn-of-the-century operettas in which merry makers chase themselves into a lather of irony and infidelity.

Virtually plotless and filled with loose ends, the comedy employs a three-tiered structure to give its readers their bearings. At a "still marauding sixty plus," novelist Scrope Townshend and his ex-paramour, high-fashion editor Laura Tench-Fenton, are suddenly tossed in a tempest: his married daughter Sibylla and her "huge" stepson Alec are courting marital disaster. Sibylla is enchanted by Alec's best friend Charles, and Alec finds himself in another quandary: Charles' girlfriend Amy has the hots for Alec! Serving less as a Greek chorus than a daffy peanut gallery is Scrope's grandson Richard and his freshman bed mate, Mimi, who gets around, to put it mildly.

Scrope and Laura are like two old war horses, driving each other to distraction to discover if the old magic is still there. The incorrigible Scrope suggests an article about adultery for her magazine to be called "Your Neighbor's Wife, Her Acquisition and Care (And What She Can Do To Help)," to which Laura sighs "was he totally unteachable?" and then remembers all Scrope's romantic misadventures while he was always protesting "there wasn't a heroine in his uncollected works that didn't mirror her!" Wondering if Sibylla and Alec are repeating history or acting as proxies for their present behavior, they form a wisecracking alliance, probably more for their own sakes than for their children.

The other relationships are equally, almost campily combative. Sibylla spies her professor husband Alec and asks, "But what have you been doing, to be this great tedious tired hulk from, all suddenly? . . . Poor catnip darling, having to fend off sophomores!" When Sibylla finally makes the move into Charles' bed, Charles asks, "What is the fuss -- it isn't as if we suddenly love Amy and Alec in the least the less!"

And when Amy declares her long-standing adoration of Alec in a hilariously long monologue, it's less a compliment to Alec than a complete demolishing of the lunk: "It wasn't an adulterous crush ever, just I used to carry your latest published poem around with me in my handbag. For company . . . I don't think I always really read the poem of yours I was faithfully carrying around, I just blissfully felt I knew you by heart, you see how dopey? Oh well, Charles says since Joyce even freshman girls have epiphanies."

Spackman, the author of An Armful of Warm Girl, is such an eccentric stylist that he may be considered an acquired taste. (The continuous exclamations, odd rhythms, and run-on nature of the sentences take some getting use to.) But he's never so off the beat that one loses the beat. ("Black chiffon isn't to sleep in, it's to sleep with in.") The character's exchanges are so long and dense and intricate that it's easy to get lost in all the verbal haranguing. From pillow talk to luncheon gab, the "delicious" girl- women take center stage and hold court to lounging hunks who come up with an occasional grunt or even a less occasional rejoinder like "which side of this dizzy debate with yourself are you planning to end up losing!"

The lack of narrative push also contributes to the lack of focus, but surely this is Spackman's point and forte: everything and everyone is slightly off, daft. But the marvelous Spackman dialogue, with its ironic asides, stream of consciousness nonsense, and brackets of affection should be patented. It begins with a sneeze of a conceit, then erupts into a full rip-snorter, taking surprising turns and unexpected dives until it disappears down a madhatter's chute:

"My blessed woman, (Scrope) besought (Laura), ''hasn't it even occurred to you that one of the bonds of long and happy understanding between us mayn't be that simply we find it natural to be in love with two people at once, provided one of them is the other of us? It's what we did! -- what's more, if everybody else did too, don't we privately think la condition humaine would be as happy a state as ours has been? Dammit, if I ever decided to rearrange the past with an autobiography, I'll say so! (By the way, I've a splendid title, Bygones, Begone!)"

This is the crucial passage in Spackman's roundelay. Nothing is resolved in his celebration of the roving eye; only the chaser, the chased, and, happily, the chase remain.