The story of tía Tula, a young woman who chooses to remain unmarried and dedicate her life to caring for her sister's children. After the death of her sister, Rosa, Tula takes on the role of mother to Rosa's children, Ramiro and María. She finds fulfillment in her role as a caregiver, but she also struggles with the temptation to marry her brother-in-law, Ramiro. Ultimately, she chooses to remain celibate, believing that marriage would玷污 the purity of the relationship she has with her niece and nephew. The novel explores themes of sacrifice, love, and the nature of family.