Numbuh 3 (Kuki Sanban) is a cute slender, happy-go-lucky, 10-year-old Japanese girl who is in charge of Diversionary Tactics and is Medical Specialist of Sector V. She is the youngest and one of the only girl members alongside Numbuh 5 in her sector.
Numbuh 3's usual outfit is an over-sized green shirt, black leggings, green socks, and black and white chucks. She has long black hair with bangs. Her eyes are very thin, almost appearing closed most of the time, although she does open them wider on occasion. She has more alternative costumes than any other characters in the show.
Numbuh 3 is described as the "airhead" of Sector V, with a short attention span, but long on charm, speaking in an Asian accent, and often alludes to her being Japanese. She is girly, optimistic, bubbly, dizzy-headed, clueless, kind, caring, patient, gentle, and arguably smarter than her teammate, Numbuh 4, upon whom she harbors a crush, as seen throughout the show.
She loves Rainbow Monkeys, which she collects, fantasizes about, and has extensive knowledge about. Due to her great love for Rainbow Monkeys, she will often irrationally defend them, occasionally allowing her insanely aggressive side to show (generally accompanied by her face turning red, teeth and ears becoming pointed and eyes flaming, resembling an oni, a Japanese demon). Despite being generally good natured, she will occaisionaly have similar explosive tantrums when she is ignored or doesn't get what she wants.Like Numbuh 5, Numbuh 3 also has a motherly side, as shown in Operation: C.A.M.P.. and she heard about the big Secret Numbuh 478's been keeping a long time ago. She heard that Numbuh 478's Officially Ticklish. So she's decided to tickle him.