George (one of the two protagonists in John Steinbeck's novel Of Mice and Men) gives Slim two very specific reasons as to why he and Lennie travel together.
"Sure," said George. "We kinda look after each other." He indicated Lennie with his thumb. "He ain't bright. Hell of a good worker, though. Hell of a nice fella, but he ain't bright. I've knew him for a long time."
Slim looked through George and beyond him. "Ain't many guys travel around together," he mused. "I don't know why. Maybe ever'body in the whole damn world is scared of each other."
"It's a lot nicer to go around with a guy you know," said George.
George, therefore, offers Slim an answer very similar to the one he offers the Curley about why he and Lennie travel together. Curley is accusing George of taking advantage of Lennie. George feels the need to offer a very limited answer though.
"We travel together," said George coldly.
"Oh, so it's that way."
George was tense, and motionless. "Yeah, it's that way."
The story George tells the boss about why they travel together is given because, he (like his son), are questioning the relationship.
"Well, I never seen one guy take so much trouble for another guy. I just like to know what your interest is."
George said, "He's my... cousin. I told his old lady I'd take care of him. He got kicked in the head by a horse when he was a kid. He's awright. Just ain't bright. But he can do anything you tell him."
The boss turned half away. "Well, God knows he don't need any brains to buck barley bags.