Masako Yashiro (矢代まさこ, Yashiro Masako; born January 13, 1947) is a Japanese manga artist. An artist of both shōjo manga (manga for girls) and shōnen manga (manga for boys), her 1970 manga series Secret Love (シークレットラブ; Shīkuretto Rabu) has been described as the first manga in the yuri (female-female romance) genre.
Source: “Masako Yashiro”, English Wikipedia (CC BY-SA 4.0), excerpt