This section of the book Lolita depicts the nuptials between Humbert and Charlotte, and it allows the reader to get inside Humbert's head to discover - as if readers didn't already know - the real strategy behind this wedding. He is cunning, and ruthless in his ruse. But it's fascinating.
At the outset it is worth reviewing briefly the style of Nabokov's work, because it creates a wonderland of mental images for the alert reader (and even for the reader who is perusing through or skimming through). Indeed, Humbert explains his actions with such narrative attention that the reader is taken on a journey of images that transcend mere male-female interaction and male longing for female attention. There is plenty of that. Enough of that in fact to make me, an adult male reader (who had at one time a crush on a girl that was young to be legal) become sensually aroused.
Of course Humbert also mocks himself and has fun with his own alliteration and ironies, and the Chapter 18 narrative is typical. He says, while speaking to Lolita on the phone (p. 74) - he is "trembling and brimming with my mastery over fate" during the phone call - that he was going to marry her mother. But this is a twelve-year-old girl, and fun is on her mind at the camp, not the thoughts of a grown woman being courted by a lecherous older man.
Still, readers on p. 74 learn that with the aid of some quality booze (and his "natural resources" - i.e., the ability to play the role he must play since he doesn't love Charlotte) he will be able to "avert any embarrassment" that showing his "indifference" to Charlotte would cause. Oh, Charlotte is ugly compared to sexy little Lolita; he...