When San was a baby, the wolf goddess, Moro, attacked her parents, who were found damaging the forest. San's parents threw her to Moro as a sacrifice to save their own lives. Moro raised San as her own daughter, and in turn San treats Moro as her mother and Moro's two natural pups as brothers.
San’s primary concern is protecting the forest and the animals she lives with. San rejects her own humanity and even thinks of herself as a wolf. She has attempted to assassinate Lady Eboshi of Irontown many times, as San believes that Eboshi’s death will result in the end of Irontown and human growth into the surrounding forest. It is only by Ashitaka's affection to her that she slowly comes to acknowledge her human side as well.
After the battle for the Forest Spirit's head, San tells Ashitaka that he is very dear to her. However, she cannot forgive the human race for what they have done to the forest and will continue to live apart from them. San returns to the forest while Ashitaka remains in Irontown. Although, before separating Ashitaka promises that he will always be near and he will visit her in the forest whenever he can and San agrees. [Source: wikia]
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