Yuka looks childish and spoiled, but she is president and CEO of Kagura Total Security. She rarely goes out on missions, but when she wants to, she can be very brave... sometimes. Her specialty is a crossbow. It's also been implied that she is older (by what degree is unknown) than she appears, and has been with Kagura the longest out of anybody (in the manga, she is shown in the background of a ruined photo of the first Kagua group).

(Source: Wikipedia)