Eiko began her career with the advertising division of the cosmetics company Shiseido in 1961 and won Japan's most prestigious advertising award four years later. Eiko was discovered by Tsuji Masuda who created Parco Ikebukuro from the ailing Marubutsu Department Store. When Parco did well and expanded to a Shibuya location in 1973, Eiko designed Parco Shibuya's first 15-second commercial for the grand opening with "a tall, thin black woman, dressed in a black bikini, dancing with a very small man in a Santa Claus outfit". She became deeply involved in Parco's image. Her last Parco campaign involved Faye Dunaway as "face of Parco" wearing black, on a black chair against a black wall, and peeling and eating an egg in one minute as "a film for Parco." She became its chief art Director in 1971 and her work there is noted for several campaigns featuring Faye Dunaway and for its open and surreal eroticism. In 1983 she ended her association with Parco and opened her own design firm.