Early life Yamaguchi was born in
Kōchi, Kōchi,
Japan. She attended
Joshibi University of Art and Design where she studied
industrial design.
Sanrio tenure Yamaguchi joined
Sanrio in 1978. In 1980, Yamaguchi won an internal design contest with her design of Hello Kitty playing the piano, and would become the third primary designer of Hello Kitty. In addition to her work on Hello Kitty, she served as the designer for the Sanrio characters Dear Daniel and Charmmy Kitty, She also created the illustration for
TV Asahi's official mascot, Go-Chan. In February 2026, Sanrio announced that Yamaguchi would step down after 46 years as Hello Kitty's designer. She was succeeded by a designer introduced under the pen name Aya. Yamaguchi will remain with Sanrio as an advisor. ==References==