Lately, the Booker Prize-winning novelist Ian McEwan seems to have developed a peculiar fascination with botched first couplings and penile misadventures. His last novel, “Solar,” boasted a cringe-making scene featuring a frostbitten phallus’s unfortunate encounter with a zipper. The novel before that, “On Chesil Beach,” set in 1962, builds to a tragic moment of fumbled copulation between two virgins that ends a marriage on its first night, recharting the lives of the main characters.

His new novel, “Sweet Tooth,” set in 1972, features multiple awkward first couplings between the main character, Serena Frome, and a series of lovers. (“I lost my virginity in my first term, several times over it seemed, the general style being so wordless and clumsy. . . ”) A description of one such encounter, narrated by Serena, features the line: “He turned out to be a tender and considerate lover, despite his unfortunate, sharply angled pubic bone” — an unexpected sequence of words the first time you encounter it, and a wholly unforgettable one when, for reasons that I can’t reveal without giving away a twist, you encounter a variation of those words a second time.