Curley’s the antagonist – because he’s the bad guy and the villain. Curley puts roadblocks in the way of the protagonist, a.k.a. George. Whenever George gets even slightly comfortable about the job situation on the ranch, Curley shows up and antagonizes Lennie and George. When Curley punches Lennie and Lennie crushes Curley’s hand, George knows that Curley can get the two of them fired. Curley’s wife is also trouble for George and Lennie, but mainly because of her husband’s attitude. If Curley were calm and not an angry man, his wife’s talking to the men would be no big deal. And when Lennie accidentally kills Curley’s wife, it is Curley’s attitude that brings disaster – he is much more interested in killing Lennie than in mourning his wife. He is angry, vindictive, and violent.