Mashiro Kuna (久南 白, Kuna Mashiro) is the former lieutenant of the under , and is currently a member of the .
Mashiro's appearance is that of a young woman with hazel eyes. She wears a white bodysuit with orange gloves, boots and scarf, along with a set of goggles atop her lime green hair. Her overall style of dress is reminiscent of the costumes worn by the in late 1970s Japanese television shows. During her time in she wore the standard robes, though her sleeves were very long. She also wore a pink scarf and a pair of glasses perched atop of her hair, which was wavier then.
Despite having formerly attained a position in the elite Gotei 13, Mashiro has very childish and immature mannerisms. She is portrayed as rather flighty and rarely takes note of the bigger picture around her. She is prone to throwing fits over the smallest of things, such as befriending or when Kensei insisted on following his subordinates into battle. Her childish personality frequently irritates her former captain Kensei, causing him to question why he kept her as a lieutenant at the time, he has noted she is capable of annoying him even while asleep (shown that his division had to hold him back constantly from trying to kill her). She often calls Ichigo "Berry-tan" (Berry Boy in the English manga, Carrot-Top in the English dub anime), a play on Ichigo's name. She seems to be good friends with Hachi, instantly disliking it when Orihime befriends him. In battle, she is somewhat more serious though, acting slightly like a superhero while attacking and after winning.