The two main characters in "Hills Like White Elephants" are depicted almost entirely through dialogue. The reader knows very little about the details of their lives. The man is American and unnamed. The girl is of unknown nationality, and the man calls her "Jig," which may be an abbreviation of her name or a nickname.
While external details remain sparse, the reader learns a fair amount about the lifestyle, personalities, and priorities of these people by listening to their tense, laconic conversation. They appear to be aimless drifters, with enough money not to have to work. The girl remarks, and the man agrees:
That's all we do, isn't it—look at things and try new drinks?
This, in Hemingway's typical style, says a lot about both of them in a few words, not only revealing their lifestyle but showing that the man is content with it, since he does not see that life has much more to offer, while the girl is restless and unsatisfied.
The man's selfishness and the girl's dependence on him, emotional if not financial, are depicted in the subtly insistent way he pushes her to make a decision (which most readers have presumed is to have an abortion). His studied appearance of indifference is at odds with the way he keeps harping on the subject of the operation, until the girl has no option but to reveal the extent of her distress.