Her birth year is unknown. The wife of the head of the Yoshioka family, senior retainers of the Otomo clan, her husband was killed in the 1578 Battle of Mimikawa. After his death she took Buddhist vows under the name Myorinni and, acting as guardian for her son Yoshioka Munemasu, effectively took charge of Tsurusaki Castle. In December 1586, when the Shimazu army invaded Bungo Province and castellan Munemasu was away defending Funai (present-day Oita City), Myorinni was left to defend Tsurusaki Castle with only elderly retainers and a handful of farmers. She trained the farmers in the use of firearms and employed ingenious tactics -- setting up decoy positions and traps around the castle town -- reportedly repelling the advancing Shimazu forces sixteen times. She ultimately surrendered the castle on condition that the lives of her defenders be spared, and her skillful defense is said to have won praise even from the opposing Shimazu commanders. She is believed to have died in 1591.

A woman of both cunning and courage who, despite losing her husband in battle, remained unshaken and confronted a vastly superior army with only elderly retainers and farmers at her disposal. Her skill as a tactician -- training defenders in firearms and devising ingenious ruses -- reportedly won admiration even from the enemy commanders.

The tale of a woman who effectively commanded a castle and repelled a great army sixteen times is passed down today as a celebrated story of feminine valor in the Sengoku period, her name remembered alongside the ruins of Tsurusaki Castle.