Apart from her brother Gregor, Grete is the only other character addressed by name in the story, a distinction that reflects her relative importance. Grete is also the only character to show pity for Gregor through most of the novella (his mother also exhibits pity for him later in the story), apparently owing to the great affection Grete and Gregor had for each other before Gregor’s transformation. Consequently, she becomes Gregor’s primary caretaker. She brings him food, cleans his room, places his chair by the window so he can see out to the street, and comes up with the idea of removing his furniture so he has more room to scurry and climb. In this role as caretaker she serves as Gregor’s only real human contact for most of the story, and she acts as Gregor’s only strong emotional tie to his family—and indeed to the rest of humanity.

Grete, however, changes more than any other character in the story—in essence undergoing her own metamorphosis from a girl into a woman—and that change occurs while her pity for Gregor slowly diminishes. While at first Grete takes care of her brother out of kindness, eventually she comes to regard the job as a duty. She doesn’t always enjoy it, but it serves to define her position in the family, and she becomes territorial about caring for Gregor, not wanting her mother to be involved. As she matures and takes on more adult responsibilities, most notably getting a job to help provide for her family financially, her commitment to Gregor diminishes. Eventually she comes to resent the role, and it is Grete who decides they must get rid of Gregor. The story ends with the parents recognizing that Grete has become a pretty young woman and thinking that it may be time to find her a husband, suggesting Grete has completed her own transformation into an adult.