Hailing from a rival household of equal wealth to the Hanaukyo family, Ryuuka Jihiou's inheritance hinges entirely on marrying the Hanaukyo head. This condition sparks immediate frustration, amplified upon learning the current heir, Taro Hanaukyo, is a young boy she dismissively dubs a "whiny midget." Her resentment targets both the imposed marriage and Taro's perceived immaturity.

Ryuuka possesses a sharp interest in military affairs and a blunt, short-tempered personality; these traits sometimes serve her well in confrontations. A fiercely competitive nature drives her to challenge Mariel, the Hanaukyo head maid, aiming to surpass her skills and prove her own worth. This ambition propels Ryuuka to enter service within the Hanaukyo mansion itself.

Her initial hostility toward Taro gradually lessens, transforming into a degree of fondness often obscured by her pride. Integrating into the household staff, she eventually rises to lead the Physical Health Department (お側御用隊, Osoba Goyou-tai).

Her background includes managing a large staff within her own family estate, though notably composed of handsome male servants, contrasting sharply with the Hanaukyo's predominantly female staff.

Across various series narratives, she experiences an accidental kiss with Taro during a moment of confusion. Later adaptations visually emphasize her fiery disposition by depicting her as a redhead. She exhibits a distinctive noblewoman's laugh and utilizes improbable storage methods for large objects, termed "Hyperspace Arsenal."

Ryuuka's journey progresses from an outsider bound by familial duty to a functional, albeit temperamental, member of the Hanaukyo staff. She finds a defined place within its unique structure while steadfastly retaining her core assertiveness and militaristic passions.