She found San and her parents with other travellers damaging through her forest when San was a baby. When she was about to attack San's parents they threw their own baby at her feet as a sacrifice for her so they could save their own lives and run away. So instead of eating her she raised San as her own and taught her to fight, act and be like a wolf. Soon San began to reject her own humanity and believe that she was a wolf.
Moro has long white fur, olive eyes with red whites (possibly because of being bloodshot), large teeth and a purple-brown nose. She is relatively big as when she is sitting down, San is as tall as her head. She also has two tails.
She seems to be a intelligent and strong wolf who would do anything to save her home forest and to save the Forest Spirit. Moro has a deep hatred for humans and dreams of the day she would finally crunch the head of Lady Eboshi. However, above all else, Moro is a very motherly and caring individual. Despite her hatred for the humans she cares greatly for San, and has still has some respect for Eboshi. She is also mildly sardonic.
She is the mother of San. She treats San as her own just like her pups. When Lady Eboshi was about to shoot the Forest Spirit's head off she was going to save the energy to chomp the head of the gun woman's head off she used it to save San instead from Lord Okkoto.
She harbours a deep hatred for her and would do anything to crunch her head off. After the Forest Spirit's/Shishi Gami head was shot off her head came back to life just for a short time and chomped off Lady Eboshi's left arm off and her head was disintegrated after.
Like any other ancient forest gods they all hate humans and just like San she hates him but eventually she told him that can he save the girl he loved then she finally herself and her clan was avenged by Ashitaka. So it might be possible that Ashitaka is trying help and save the forest and to end the war between the forest and the humans.
It seems that she and Lord Okkoto are friends and he is only forest god that could only understand what she is talking about and feeling.
All those years she guarded and protected the great Forest God, she thought he might be able to save her. Instead, he ended her suffering by a single kiss.