In This Side of Paradise, how does the narrative style change in Book Two, Chapter 1?

The narrative is now presented in a form of dramatic writing: in dialogue form with stage directions. Rosalind Connage, Alec's sister, is coming out (an occasion marking a girl's entry into debutante society) at the Connage house in New York, and Amory is present. We learn from stage directions and from her mother, sister, and brother's comments as Rosalind prepares that Rosalind is a beautiful, sophisticated, somewhat spoiled and self-involved girl. Amory accidentally enters her dressing room and the two converse like professional socialites--a conversation that has rules. They kiss after several minutes. Rosalind boasts that she was expelled from Spence, her school, and that she has kissed dozens of men and will probably kiss dozens more. Amory distinguishes between a sentimental person, who thinks that things will last, and a romantic person, who hopes that they won't. He leaves wanting to kiss her again but Rosalind refuses, saying that she has won their exchange.

Rosalind's mother reappears, explaining to her daughter the ways to lure a wealthy a man, like Dawson Ryder, and urges her to follow the rules. Several hours later Rosalind dismisses a former beau, meets Dawson, and then falls in love with Amory. The novel shifts back to traditional narration and describes how the two spend several intense months being completely in love. Amory takes a job at an advertising agency in an attempt to make enough money to satisfy