What does sharing the goose with Kat symbolize in the book? support with references

They both feel a sense of camaraderie and brotherhood. They share the satisfying meal in a ruined building at night under the stars. They mean to each other more than their natural families do. The scene is simple yet profound. There is a love for each other in a momentarily peaceful setting against the backdrop of a brutal war. The meal is the first satisfying one that they have had in a long time.