Curley's wife, like the other players in the drama, is simply a character type and the only woman in the plot. She is defined by her role: Curley's wife or possession. George and Candy call her by other names such as "jailbait" or "tart." She wears too much makeup and dresses like a "whore" with red fingernails and red shoes with ostrich feathers. Lennie is fascinated by her and cannot take his eyes off her. He keeps repeating "she's purty." George, realizing Lennie's fascination, warns him to stay away from her.
Curley's wife knows her beauty is her power, and she uses it to flirt with the ranch hands and make her husband jealous. She is utterly alone on the ranch, and her husband has seen to it that no one will talk to her without fearing a beating.
Steinbeck's initial portrayal of Curley's wife shows her to be a mean and seductive temptress. Alive, she is connected to Eve in the Garden of Eden. She brings evil into mens' lives by tempting them in a way they cannot resist. Eventually, she brings about the end of the dream of Eden, the little farm where George and Lennie can live off the fat of the land. Her death at Lennie's hands means the end of George and Lennie's companionship and their dream. She is portrayed, like the girl in Weed, as a liar and manipulator of men. In the scene in Crooks' room, she reminds Crooks of his place and threatens to have him lynched if he doesn't show her the proper respect as the wife of the boss' son and a white woman. All of these appearances cause the reader to dislike her and see her as the downfall of the men in the story.
In the barn scene, however, Steinbeck softens the reader's reaction to Curley's wife by exploring her dreams. Her "best laid plans" involved a stint in the movies with all the benefits, money, and pleasure that would provide. Her beauty is such that perhaps that dream might have come true. Her dreams make her more human and vulnerable. Steinbeck reiterates this impression by portraying her innocence in death:
Curley's wife lay with a half-covering of yellow hay. And the meanness and the plannings and the discontent and the ache for attention were all gone from her face. She was very pretty and simple, and her face was sweet and young. Now her rouged cheeks and her reddened lips made her seem alive and sleeping very lightly. The curls, tiny little sausages, were spread on the hay behind her head, and her lips were parted.
Steinbeck seems to show, through Curley's wife, that even the worst of us have our humanity.