☓༝. Mizu ⚔︎.༝☓

Mizu was born in Japan around 1637-38 to a Japanese woman who was raped by a white Western trader. There were only four such men in Japan at the time of her birth, and all Westerners had officially been forbidden from entering the country since 1633. Due to being seen as a half-breed monster or demon for her heritage, Mizu has usually concealed her blue eyes with a wide-brimmed hat and tinted glasses, though she does not need them to aid her vision.

Shortly after her birth, Mizu was targeted by an assassination attempt, which claimed her mother's life instead. She was given to a maid, who posed as her mother, by an unknown individual, and taken into hiding at the fishing village of Kohama. As a child, she lived with her "mother" in a hut at the edge of the village, forbidden to go out or the bad men would find her. Though they had moments of warmth, her "mother" became increasingly addicted to opium at the brothel she worked at, hitting and reprimanding Mizu if she even went near the windows. She eventually shaved Mizu's head to make her resemble a boy, since she claimed the bad men would be looking for a girl.

One day, while her "mother" was in a drugged stupor, Mizu ventured out and encountered several local children, who were frightened by her unusual appearance: her more rounded blue eyes were usually only depicted in oni or other dangerous supernatural beings in Japanese folklore. Soon after, her hut was set aflame. She escaped, but having heard her "mother" screaming and unable to find her afterward, assumed she was dead. Although she made a grave marker for her "mother" and swore to avenge her even if it cost her life, Mizu was left with no options but to scavenge the refuse-heaps and gutters of Kohama to stay alive, hiding her eyes behind a makeshift mask and growing her hair back. The town children, led by Taigen, mercilessly bullied her, eventually chasing her to a cliff's edge during a rainstorm and tearing off the mask, comparing her eyes to a dog's and calling her "mother" a whore who killed herself for bedding a white devil. When she unexpectedly lashed out in response to their cruelty and fought them, Taigen prepared to bash her head with a rock, but he and the others were suddenly frightened off by a meteorite that crashed into the cliff nearby.

Mizu is led by her mind, much more than her heart. She is quiet, calculating, independent, strategic, confident, dismissive of any emotions, and extremely vengeful, so much so to the point she’s called an Onryō of Japanese folklore [vengeful demon-ghost of a wronged woman] a few times in the show and in The Tale of the Ronin and the Bride, is metaphorically implied to be one [A direct reference to her experience with Mikio]. Though she has a talent for manipulating people into giving her information and is capable of stealth when necessary, Mizu often takes reckless, brazen risks to reach her goal, usually relying on her sheer skill in combat and infiltration to overcome any obstacles rather than planning around them. While she does usually overcome said obstacles, this approach is not foolproof, and has often left her with serious injuries or alerted enemies. In at least two circumstances, she almost certainly would have died if not for Ringo's timely assistance.

She cares nothing for the fate of the larger world or communities around her, viewing all powerful individuals as privileged and corrupt. She holds Akemi in contempt initially due to her wealthy status and impulsive willingness to throw it away for Taigen, and doesn't bother to help her when she is captured by her father's men. In the Season One finale, Mizu is also indifferent to the fate of Shogun Ito despite seeking to kill his enemy Fowler, blaming the Shogun for covertly letting Fowler into Japan in the first place. After the tragic end of her marriage (perhaps the only brief time in her adult life when she felt happy), Mizu's only goal is fulfilling her personal quest of revenge, even if she dies in the process; she tells Heiji Shindo "I have no interest in being happy... only satisfied."

Mizu struggles with self-loathing, due to the social limitations placed on her by being a woman (hence her practical decision to give herself more flexibility by disguising herself as a man), and the ostracization she has always faced due to her 'foreign' appearance, blaming it entirely on her unknown white father. She often dubs herself a 'monster' for her heritage, but ironically has only reinforced this perception of her- though less by her appearance and more by her cold, aloof personality, brutal and unorthodox style of combat and relentless drive for vengeance at the expense of everything else. For all her emotional control in combat, certain insults trigger her, particularly comparisons to the Onryō of Japanese folklore causing her to lash out violently in response. In hating herself as a 'monster', Mizu often forgets Eiji's unconditional acceptance and teaching of her as a child despite any physical or personal 'flaws' (she fears he was only so accepting because he was blind)- particularly his mantra that "the strongest sword is a blend of steel, pure and impure."

Due to the trauma she endured as a child and as an adult, Mizu is highly mistrustful of people in general, and avoids making emotional attachments, seeing them as distractions from her quest for revenge. She does sympathize with the underpriveleged and fellow social outcasts (such as her disgraced husband Mikio, the handless Ringo, the blind Eiji, and Madame Kaji's prostitutes) but avoids involvement, and certainly does not make assurances for bystanders' safety unless she has given her word or they are part of her plans. While she increasingly treats Ringo with respect and allows herself to trust him enough to keep her secrets (though Ringo only discovered her identity by accident) and assist her, she avoids becoming close to him as a friend. She scorns Taigen's bushido codes of honor and chivalry and is willing to take any opportunity to strike she can, not trusting others to honor their agreements. The only people she has ever allowed herself to love unconditionally and be completely vulnerable with, are her 'mother' and her husband Mikio, both of whom ultimately betrayed her trust in multiple ways. Unable to determine or care which one gave her away to bounty-hunting samurai, Mizu's trauma from this provoked her to leave her mother to die, and then kill Mikio in cold blood when he followed her- leaving her with nothing but loneliness, grief and mistrust. Ultimately, she walled these emotions up behind her childhood desire for vengeance, seeing it (at first) as the only way to move forward.

However, despite cultivating a cold, indifferent personality, Mizu is certainly not heartless. In the first episode she shows kindness to a mother and daughter who were unable to get into Kyoto by giving them the gold hairpin that she took from Taigen in their first duel. Despite having been away from Master Eiji for some time, she voiced prayers for his safety and health at a Shinto shrine on her journey, indicating how much she cared for him. She saves Taigen many times despite being enemies, and in the finale tells him to seek his own safety and that his pursuit of the life of a samurai will only get him killed. She also continues to show relative kindness to Ringo, her apprentice. When she mercy-killed Kinuyo at Madame Kaji's request (in exchange for information), despite knowing she was saving the girl from a much more prolonged and painful fate, she held Kinuyo's body for several moments afterwards, with a look of pain and remorse.

During Abijah Fowler and Heiji Shindo's coup, Mizu intervenes to divert Fowler from killing the Shogun's son, saving his heirs as well as Taigen and Akemi. When Fowler points out to her that Edo is burning "in a blood sacrifice to your revenge" (since she set Edo Castle alight while pursuing him) she shows shock and regret over the destruction she inadvertently caused, in contrast to her earlier dismissal over the fate of the Shogunate. Despite her vengeful rage toward Fowler, when she finally corners and cripples him, she ultimately decides not to kill him yet due to his possible use in tracking down her other two potential fathers, showing that she is beginning to act with more strategy and less brazen impulse- and to learn and care more, about the wider world she once viewed with total indifference.

Mizu is a tall, slender woman with an athletic build, blue eyes, an oval shaped face with a pointed chin and long black hair which she ties up in a bun. Her regular attire, a male disguise consists of orange tinted spectacles with round frames, to mask her blue eyes, dark grey arm warmers, a dark blue haori tied with a lighter blue obi, baggy black trousers, with darker black stockings and sandals, a white scarf tied around her neck to disguise her lack of Adam's apple (which she later exchanges for Taigen's orange scarf) and a plain brown kasa (large hat) with a dark blue cape, when traveling outside in cold conditions. Mizu nearly always carries a blue-tinted katana made of meteorite ore, with a wave pattern along the edge, which she wields in battle. She stops carrying it after Episode 6 when it is broken, melting it down to re-forge a new sword when she is ready. During her married life with Mikio, she wore a dark blue women's kimono with socks and sandals.