Sasaki Rui

was a Japanese swordwoman, onna-musha, and kenjutsu expert of the early Edo period (mid-17th century). She was known as the "Strangely Dressed Female Sword Master".

Life Sasaki was born in Koga Domain, located in Shimōsa Province (modern day Koga, Ibaraki); her exact birthdate is unknown. Her father Sasaki Uōto was a member of a clan of kenjutsu masters in service to Doi Toshikatsu and was thoroughly versed in the martial arts. Since Rui had no brothers, and her attempts to take a husband ended in divorce, upon her father's death from illness the Sasaki clan name became extinct.