Born 1 January 2231 Age 17 on the colony planet Workoh, Kei could be described as a tomboy. Born a redhead (with bleached blond bangs), Kei is hot-headed, impulsive, and rude, and because of this is often mistaken for being a man. Those who mention this are, as expected, reminded (painfully) that she is, in fact, a woman. Her usual response to a crisis is "shoot first and ask questions later." But, can show insight into situations when properly motivated. She usually gets into a lot of arguments with Yuri over her "girly" attitude, but is usually the first in line to back her up when trouble happens. Kei is also very Proficient with a Blaster and uses one as her Primary weapon.

Unlike Yuri, Kei has a love for cheap thrills: jet coasters, fast-food restaurants, drinking beer, sushi, and big-game fishing. She dislikes wearing dresses, as evident when she, Yuri, and Touma were stranded on World's World and the Lovely Angels were temporarily placed in an all-girl high school, where uniforms with skirts were mandatory.

Kei is afraid of nothing...except for ghosts, zombies, and vampires, which she is completely terrified of. She also dislikes showing her softer side, which she does have, as apparent when she had to protect a young baby being chased by assassins. During a crisis, she had allowed the baby to suckle her (even though she wasn't lactating) in order to keep him quiet when the assassins were close by.