Teto was found by Nausicaä's mentor and Jihl's good friend Lord Yupa. He saw Royal Yanmas carrying him off and Yupa thought that it was a human child. So he killed the Yanma's and rescued Teto's life. This angered the Yanmas and they chased him out of the forest. Nausicaä saw this and rescued Yupa by using strobe grenades and her worm flute. Fox squirrels usually don't take to people, but Nausicaa let Teto bite her on the finger to show him her good intentions.
Right before spotting the Pejitei Brig, Nausicaä and Mito were flying in the Valley Gunship when she heard a psychic cry. She became so absorbed with the call that she forgot she was flying. Teto jumped on her face and broke the psychic connection , thereby saving her life.
Teto also helped find Nausicaa's backpack when both she and Asbel fell into the safe inner regions of the Sea of Corruption. Unfortunately, Teto dies from radiation poisoning, while he and Nausicaä were being held afloat by the God Warrior.
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