Keiko Masuda (増田 恵子, Masuda Keiko) (born Keiko Kobayashi (小林 啓子, Kobayashi Keiko) on September 2, 1957 in Shizuoka, Japan) is a Japanese pop singer and actress. She is better known by her nickname Kei, and is one half of Pink Lady, the top idol group in Japan in the 1970s. In the United States, they are known for their self-titled TV program. Masuda is represented by her own management firm Kei-Office (ケイ・オフィス, Kei Ofisu).