Who is George talking about when he says "I'm scared I'm gonna tangle with the bastard myself. I hate his guts"? What is the intended effect on the reader of this statement just as the chapter closes?

Curley has come into the bunkhouse to measure up Lennie and George. He visits them on the pretense that he is looking for his wife. Curley has a major case of small guy complex. He deems George as somebody he could possibly beat up. George senses this and fears he might have no choice but to tangle with Curley. The scene casts a depressing gloom over the ranch and foreshadows threatening days to come.