Mito grows up in the Valley of the Wind and becomes a retainer for King Jhil. When Jhil suffers bad health, he becomes Nausicaä's retainer. He co-pilots the Valley Gunship during the Periphery Campaign. When the Valley Forces are separated from Nausicaä, he takes over as pilot. Mito succesfully gets permission from Kushana to leave the Acid Lakes encampment to search for Nausicaä . After the Battle of the Acid Lakes, Mito returns the Gunship to protect the Valley, while Nausicaä decides to head south with Kushana.
Upon his return, Mito finds out that Jhil has gone blind. Just before his death, however, Jhil tasks Mito with finding Yupa to help Nausicaä.