Back when the world was innocent, or at least yet to be proven guilty, many of us knew someone like Ewan Morrison and certainly like the characters who inhabit his novels. They were people we knew in the later days of secondary school or at university or who were friendly with our older siblings. A certain enviable worldliness was their distinguishing feature.

Usually these people possessed artistic tendencies and bohemian proclivities. Their personalities strayed outside the lines. They tended to own all the right albums and know the best pubs and be the keepers of all manner of tantalising and secret knowledge. One from my own youth, Ian, had drawn the sleeve of the Roxy Music album For Your Pleasure over an entire wall in his bedroom, something that, for 1979, seemed impossibly louche.

What happens when these characters find themselves forced to confront the reductions of middle-age is very much Morrison’s subject matter. All too soon, the phenomenon that Mrs Patrick Campbell dubbed the hurly-burly of the chaise longue is overtaken by the rush to source something a bit more hardwearing. Yet for some, the sexual and emotional adventuring never recedes completely. Like moral eczema, it flares up at inopportune moments. This is the central premise of Menage. In the old days, I seem to recall, a menage was a group of older women who banded together to save and invest their pin-money. Morrison has a wholly different type of unit in mind; one whose idea of indulgence stretches slightly beyond a pot of tea and a round of digestives.

Menage is in itself a third component, of a series of novels that are pleased to breaststroke their way through the deeper waters of the sexual mainstream. Swung was a lightly fictionalised account of the author’s dabblings on the swinging scene, whose enthusiasts swap partners; Distance considered sex in the imagination, sex in the face of physical separation. Like the latest, the novels could be improbably long for the weight of the subjects under consideration, getting close to 400 pages, and so they’re defiantly prolix. They are written well enough, in a functional, undemonstrative style. But with their sexual monomania and their casts of young media types fretting over their regrettable compulsions, Morrison does sometimes come over like a Jackie Collins for Guardian readers.

In Menage it’s the early 1990s and art students Owen and Saul are sharing a flat of titanic Withnail and I squalor in Hoxton, just as the Saatchi-sponsored Young British Artist movement is gathering momentum: “All I could make out among the stacks of encrusted plates,” writes Morrison “was a halved orange skin, scooped out and refilled entirely with cigarette butts, like some sick surrealist artwork.” To free up funds for more sherry and paracetamol the pair take on a flatmate, Dot, a gilded young trustafarian artist and, blow me down, what a coincidence, an eminently corruptible sexual radical who also happens to be of the opinion that camcorders aren’t just for family weddings.

What follows is, as the blurb says, a reimagining and relocation of Jules et Jim to Britpop London as the trio leap the hurdles of social convention then notice they’ve injured their ankles and skinned their knees on the way over. Nonetheless the experience is sufficiently gratifying for the three to entertain the notion of an encore in a present day which sees Dot now elevated to conceptual art superstar and the men in various conditions of drizzly, middle-aged disappointment.

How you respond to Morrison is, I think, dependent on how you regard your own salad days, when you were doused in a light vinaigrette of hope and expectation. Personally I find that his work, Menage in particular, can make make one feel ancient and suburban. It springboards from a premise that sexual extremity is a widespread, equal-opportunities pastime. Patently it isn’t, it’s a hobbyist pursuit like Morris dancing. This does not prevent a fig-leaf being attached to Morrison’s fictions. They purport to examine love in the modern world from an unusual angle. But this angle feels awkward. So awkward, the characters of this novel would struggle to match it even in their more amorously adventurous moments.

Menage, by Ewan Morrison, Jonathan Cape £12.99

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