Chizuru Yukimura, daughter of Western medicine doctor Koudou Yukimura, journeyed to Kyoto disguised as a boy after her father vanished there. In 1860s Kyoto, she witnessed rogue samurai slain by Rasetsu—humans transformed by the "Water of Life" (Ochimizu)—and was rescued by the shogunate-aligned Shinsengumi. They detained her for knowing classified secrets but permitted her stay upon discovering Koudou was their missing collaborator. She possesses brown eyes and dark-brown shoulder-length hair, typically in a ponytail secured by a white ribbon with forehead bangs. To minimize disruption in the all-male Shinsengumi, Vice-Commander Toshizou Hijikata ordered her to maintain her male disguise: a peach-pink top and gray baggy pants. Despite this, her gender was often instantly recognized. She carried a kodachi sword, a Yukimura heirloom, and received basic self-defense training. Her attire later evolved into a red, white, and black Western-style outfit. Gentle, compassionate, and humble, Chizuru seldom voiced her opinions unless driven by concern for others, such as urging Hijikata to rest during exhausting work. She performed chores like treating injuries and cleaning, forming deep bonds with the Shinsengumi. Each member's death affected her profoundly due to her loyalty and selflessness. She consistently prioritized their safety over her own, refusing to abandon them even when kidnapped or threatened. Resilience emerged in crisis, physically shielding Commander Isami Kondou or confronting adversaries like the demon Kazama Chikage, who sought to claim her. Unbeknownst to her initially, Chizuru belonged to the Yukimura Clan, descendants of a demonic bloodline. Separated from her twin brother, Kaoru Nagumo, during a human massacre of their clan, she was raised by Koudou unaware of her heritage. Following his advice, she concealed her rapid healing ability—a demon trait—to avoid persecution. This ability later confirmed her pureblood status to Kazama, who observed her wounds heal instantly. Her lineage made her a target for factions wanting to exploit her blood, either to breed pureblood demons or control Rasetsu transformations. Her development centered on reconciling human upbringing with demonic identity. Early naivety shed through exposure to war, betrayal, and loss. She witnessed pivotal events: the Ikedaya Incident, Kondou's capture and execution, and allies becoming Rasetsu. She confronted her father after learning he experimented on the Shinsengumi with Ochimizu and rejected her brother Kaoru's plan to exterminate humans. Accepting her heritage in later arcs, she upheld human values by protecting the Shinsengumi from supernatural threats. Relationships deepened, like her mutual reliance with Hijikata and their vow to survive together.