Ammu is the mother of twins Rahel and Estha, and Mammachi’s and Pappachi’s only daughter. Ammu is willful and rebellious and leaves her family’s home at age eighteen to marry Babu, a man she’s only known for five days. Ammu’s attempts to escape the confines of her life back home backfire when she discovers Babu is an alcoholic and he tries to get her to sleep with his boss to keep his job. Ammu, strong and independent, yet emotionally volatile, beats her husband Babu in response and goes back home to Ayemenem and becomes the town eccentric. Halfway through the novel, it is revealed that Pappachi abused Ammu as well as Mammachi, instilling intense fear in her as a child. 

Ammu’s frustrations and variable emotions severely damage the twins, especially Rahel, who constantly worries she doesn’t have her mother’s unconditional love. Ammu, however, is the only woman in her family, save Rahel, who acts out of love, and who gets to experience true love, with her relationship with Velutha. As Ammu and Velutha make love, time stops and she experiences something eternal and transcendent. Tragically, Ammu’s relationship with Velutha is cut short when the pressures of history, family and social obligation, and intense betrayal converge.