Kagura is a fourteen-year-old girl belonging to the Yato tribe, a race known throughout the universe as the strongest and most ferocious fighters. Born on the planet Rakuyo, she is the daughter of Umibouzu, the universe's most powerful warrior, and the younger sister of Kamui, a prominent figure in the space pirate group Harusame. Her early life was marked by family turmoil; after her older brother left home, she remained behind to care for their ailing mother until her death. Following this loss, Kagura smuggled herself to Earth, seeking a new life. There, she joined the odd-jobs business Yorozuya, living and working with the samurai Sakata Gintoki and the boy Shimura Shinpachi, who became her surrogate family.

Her personality is a striking contrast of traits. Outwardly, she presents as a lively, bold, and often crude girl with an extreme and eccentric sense of humor, not hesitating to engage in dirty talk or slapstick comedy. Despite her cute appearance, she is known for her incredible selfishness, competitive spirit, and a fearless, reckless nature that often lands her in the center of trouble. However, beneath this rough exterior lies a deep-seated innocence, a strong sense of justice, and a profoundly caring heart. She cannot ignore the suffering of others and possesses a fierce loyalty to her friends, which serves as her primary motivation. Her ultimate personal goal is to overcome the violent, battle-hungry instincts of her Yato blood, choosing to fight with her soul and free will rather than being ruled by her innate nature.

In the story of the Yoshiwara in Flames, Kagura plays a pivotal role. She travels to the underground district of Yoshiwara with the Yorozuya to help a young boy find his mother, only to become entangled in a conflict with the district's immortal king, Housen. It is here that she is confronted by her brother Kamui and his lieutenant, Abuto. Facing the powerful Abuto, Kagura is pushed to her limits. When Shinpachi's life is put in mortal danger, her Yato instincts fully awaken, causing her to lose control and unleash a brutal, nearly unstoppable onslaught against her enemy. This rampage represents the very fate she has always fought against, highlighting the central conflict of her character. In the end, it is Shinpachi's desperate plea that stops her, bringing her back to her senses and reaffirming her commitment to her humanity over her bloodthirsty lineage. This event also marks a significant development in her relationship with Shinpachi, who saves her from losing herself, and directly sets up her future antagonistic dynamic with Kamui, who observes the battle and coldly entrusts Gintoki to make his sister stronger.

Kagura's key relationships are the cornerstone of her character. Her bond with Gintoki is that of a father-daughter or mentor-student duo, where he provides guidance and a place to belong while she learns to control her power and follow her own path. Shinpachi acts as her emotional anchor and moral compass, often reining in her worst impulses and providing the support she needs to fight her inner demons. Her relationship with her brother Kamui is a source of great pain and a primary driver of her growth; he embodies the Yato ideals of pure strength and carnage that she rejects, and their eventual confrontations force her to prove her resolve. Her development is a continuous journey of self-control and maturity, learning to harness her tremendous power not to destroy, but to protect the new family she has found on Earth. Her notable abilities include superhuman strength, speed, agility, endurance, and a rapid healing factor typical of the Yato. She wields a large parasol that functions both as a shield against sunlight, to which her tribe is vulnerable, and as a powerful projectile and melee weapon capable of firing blasts.