Curley's wife is portrayed as a trouble-maker, especially in the scene in which she comes into Crooks' room uninvited while Candy and Lennie are visiting there. Candy tries to get her to leave because she is being flirtatious with virtually every man on the ranch, probably trying to make Curley jealous. Curley has gone into town with the other men, but they could be back at any moment, and there would be violence if he caught her in Crooks' room. She seems physically attracted to Lennie because of his size and strength, in spite of his childish mind. The fact that she knows he maimed her husband's hand also makes him attractive to her. It foreshadows the tragedy that will eventually occur.
Crooks is the most apprehensive of all because his race makes his position on the ranch precarious. He says:
"Maybe you better go along to your own house now. We don't want no trouble."
He is trying to be polite and diplomatic, but she is angered at being rejected by two of the lowest men in the social hierarchy. She also wants to assert her privileged status as the wife of the owner's son. Crooks becomes the scapegoat. She terrifies him by hinting that she could accuse him of molesting her. He immediately backs down. She says:
"Well, you keep your place then, nigger. I could get you strung up on a tree so easy it ain't even funny."
The scene is intended to do many things. It shows Curley's wife's budding interest in Lennie. It shows her capacity to cause very serious trouble, her recklessness, her tendency to roam all over the ranch trying to relieve her boredom, her frustration, and her potential cruelty.