This scene shows Candy's dog about to be shot. Candy is looking away, showing how much the dog had an impact on his life. He sees the dog as his only companion.
The theme of loneliness can be connected to Curly's wife. Despite being married she doesn't have a god relationship with Curly. All the other ranchers avoid her whenever she tries to strike up a conversation.
Simile:“Slowly, like a terrier who doesn’t want to bring a ball to its master, Lennie approached, drew back, approached again.” (Ch. 1 Pg. 9)