Baby sister of the trio, Ai has a spunky, tomboyish personality and demeanor, and has a genius-level I.Q. and is particularly adept in mechanics, computer programming and engineering. She has built a wide array of gadgets to help her sisters in their heists. A typical teenager, she seems to be preoccupied a lot and dreams of falling in love. Being a high school girl, she also has a pet tabby kitten called "Tiger."
While not as skilled as her sisters, Ai has none-the-less mastered a number of skills and is regularly the one who operates the get-away vehicles for the heists, including helicopters, gyrocopters, trucks, motorcycles, cars and mini-planes. Her greatest weakness lies in the fact she is physically the weakest of the three siblings (evident in the anime when she tried to suplex a wrestler, only to have the maneuver backfire on her), but in exchange, she is also the most agile.