At some point before gaining control of the Toyko underworld, O-Ren Ishii was given a sword made by Hattori Hanzō. O-Ren's sword was only seen being used twice. The first time was during the Yakuza bosses council meeting where O-Ren is seen decapitating Boss Tanaka for bringing up her Chinese and American heritage as a negative. The second and last time is when she and Beatrix Kiddo fight with both of their swords. The lack of a hand guard (tsuba) or handle wrapping classifies this sword as shirasaya (白鞘) (meaning: white scabbard). Shirasaya is a Japanese blade in a wood holder with a saya (scabbard) and tsuka (hilt).
Her particular sword is notable due to the sakura (cherry blossom) design on the handle (tsuka). The sakura and the cherry blossom are linked to the Japanese cultural views on the ephemeral nature of life, transience of blooming seasons, exquisite beauty, volatility, mortality, graceful acceptance of destiny and karma, nationalism and militarism. These are character traits shown by O-Ren. Shirasaya is style of sword mounting that is popular with Japanese nobility, perhaps signifying O-Ren's status as queen of the underworld in Japan.