The social setting for the vast majority of this fantastic novel for young adults is quite unromantic: it is Saint Grace's hospital, and the underlying theme is terminal illness. Both teenagers have been admitted due to their ongoing struggles with cystic fibrosis and, in Will's case, his additional battle against B. cepacia, which is a secondary condition generally considered fatal for cystic fibrosis patients.
Stella knows the hospital like the back of her hand, since she has been coming here ever since was a little girl thanks to the various trials and tribulations related to her disease. She knows many members of the staff so well that they have become her second family, and, for Stella, Saint Grace's is like a second home.
For Will, on the other hand, it is his first time at Saint Grace's. In her desperate attempt to help him win the battle against B. cepacia, Will's mother has spent the last several years dragging Will to various hospitals around the world, and, to put it bluntly, Will is sick and tired of it.
Part of any discussion about social setting should include the dos and don'ts that apply to the situation. Thanks to their respective illnesses, Stella and Will need to be at least six feet apart at all times—until Stella decides to steal back one foot, giving the novel its memorable name.