Ahn Masako is a Japanese picture book author, plastic artist, and animation professional, recognized as the original creator behind the Dosukoi Sushi Zumō series. She was born in 1975 in Gifu Prefecture, Japan, and is a graduate of the Painting Department of Tama Art University, where she majored in oil painting. Her creative practice extends across multiple disciplines, including writing and illustrating children's books, creating plastic art and puppets, and directing animated short films.

Ahn Masako is affiliated with the Japanese animation planning and production company Shirogumi, where she has participated in the production of short films and animations based on picture book stories, including the crafting of samurai armor and other sculptural forms. In 2014, her animation work titled Tapu no Yume, for which she served as puppet maker, art designer, and director, was screened at the Tokyo Photographic Art Museum. As a published author, her picture book publications include Tapu no Yume, Sora Tobu Densha, Dosukoi Sushi Zumō, and Birthday Cake, all released by Kodansha. The Dosukoi Sushi Zumō series has expanded to include multiple volumes such as Tamago no Sato no Himitsu and Ōtoroyama no Himitsu, as well as related titles like Osushi Shōgi and sticker books, establishing a recognizable brand within children's literature. Her illustration work also extends to chapter books, including the Mononoke-ya series written by Hiroshima Reiko and published by Seizansha.

In terms of adaptation history, her picture book Dosukoi Sushi Zumō has been adapted into an anime, marking her most prominent credit in the television animation medium. The work combines sumo wrestling with sushi ingredients, reflecting a playful and culturally specific concept aimed at young audiences. Her artistic identity is grounded in a background in fine arts, with a tactile approach to creation that involves hands-on work with physical materials like puppets and plastic art. This hands-on sensibility carries into her picture books, which often feature character-driven narratives with a strong visual component. Her professional significance lies in her ability to work fluidly between the realms of published illustration and animated production, a hybrid career path that bridges traditional children's publishing and the animation industry in Japan. While she is primarily an author and visual artist, her work on Dosukoi Sushi Zumō demonstrates how original picture book concepts can transition into animated formats, contributing to the cross-media landscape of Japanese content for children.