Poor George. It must be very frustrating, at least at times, for him to be traveling with Lennie, a rather oafish man with the mind of a child. In the first chapter in John Steinbeck's Of Mice and Men, George and Lennie have stopped near the river to make their camp for the night.
George is wiry and small, almost an opposite of his traveling companion. The two men travel together, working on ranches until the job runs out or until Lennie gets them in trouble (which is more likely). Lennie loves to pet soft things, which is fine unless the soft thing is the fabric of a woman's dress and he is misunderstood and feared.
Lennie is like a child imitating an admired older brother.
[George] threw a scoop of water into his face and rubbed it about with his hand, under his chin and around the back of his neck. Then he replaced his hat, pushed himself back from the river, drew up his knees and embraced them. Lennie, who had been watching, imitated George exactly. He pushed himself back, drew up his knees, embraced them, looked over to George to see whether he had it just right. He pulled his hat down a little more over his eyes, the way George's hat was.
After this display of child-like hero worship, Lennie begs George to tell him again about the farm they hope to have one day, including rabbits for Lennie to take care of. Most other men who live the life of these itinerant ranch hands have nothing to look forward to, but even George somehow wishes their dream will one day become a reality.
When it is time for dinner, George wants Lennie to go gather some wood so he can cook beans for thier dinner.
Lennie said, "I like beans with ketchup."
"Well, we ain't got no ketchup. You go get wood. An' don't you fool around. It'll be dark before long."
Lennie crashes off through the brush, splashes around in the water, and comes back with only one small twig in one hand. Immediately George knows what is in Lennie's other hand: the mouse he killed because he petted it too hard. He loves soft things, remember. Lennie denies it, and then it begins.
George rants about all the things Lennie does that drive him crazy. It is an understandable rant, but it is a rant nonetheless. George is frustrated because Lennie does not listen, because he forgets everything, because he makes the same mistakes time after time, and more. What George does not say, though it is true, is that he knows Lennie is not capable of doing better at any of these things, and that is what is most frustrating.
When George finally takes a breath, Lennie speaks.
"George," very softly. No answer. "George!"
"Whatta you want?"
"I was only foolin', George. I don't want no ketchup. I wouldn't eat no ketchup if it was right here beside me."
"If it was here, you could have some."
"But I wouldn't eat none, George. I'd leave it all for you. You could cover your beans with it and I wouldn't touch none of it."
It is a rather ridiculous thing to say, but it is the only thing Lennie has to offer. He feels bad for causing George so much grief, but he, too, knows that there is not much he can do to make things better. So, Lennie does what he can: he offers to sacrifice something he loves for his friend. It is not much, but it is all he has to offer.