One cannot isolate one moment in chapter 17 of J.D. Salinger's Catcher in the Rye when making inferences about Sally's character. In one word, her character could be identified as shallow. She and Holden meet to go to the theater, and even though she was making out with him in the cab, she appears to flirt with another boy at the play. She is willing to overlook Holden's erratic behavior so that they can go to Rockefeller Center and skate. Is it so that she can show off in a short skirt as Holden suspects?
Sally doesn't really seem to have a problem with Holden's behavior until his yelling draws attention to them. Every suggestion he makes with regard to loving her, running away, living on their own is rebuffed. Despite the fact that anyone could observe that Holden is beginning to fall apart, Sally belittles and ridicules his plans. This further emphasizes the shallowness of her character.
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