Tova Sullivan, the first protagonist of the story, is a stoic seventy-year-old woman seeking solitude in order to internalize her grief after the deaths of her son and husband. Resolutely independent, Tova blinds herself to human connection; she rejects Ethan’s advances, struggles to admit weakness, and only asks her friends for physical favors rather than emotional support. Over the course of the book, her friends reach out to her many times to offer help that she refuses. Ultimately, it is her bond with Marcellus that changes her. She senses that he is like her—isolated, torn from the life she once knew by circumstances out of her control, resigned to spend life observing the joy and growth of others. Through her relationship with the octopus, a different side of Tova is revealed. She is shown to be caring and empathetic, brave, and even humorous. With Cameron’s arrival at the aquarium, he is essentially entering a sacred space for her and she willingly shares it with him, demonstrating that even though she often seems standoffish, what she truly desires is to feel close to others once again. 

Tova’s growth as a character can be seen in the way her relationships change over the course of the story. By the book’s end she is asking her friends to help her move, happily working with Cameron, and inviting Ethan into her life as a friend and possible partner. She begins to show the same amount of care that she gives to Marcellus to the people in her life, and begins finally to accept her past and move on, supported by a network of friends and family that love her.