Otsuru (大鶴, Ōtsuru) was once a young woman living under the pseudonym "Okiku" (お菊) given to her by the Empty 7, a violent religious organization she was once an agent of. She later died by her contractor's hands after meeting Afro later in adulthood.
Otsuru started off as a young orphan of an unknown age living within an orphanage that doubled as a kenjutsu school for young men and boys. She was the only girl living in building and her prior history of birth, abandonment, or how she got there is currently unknown. After the defeat of the former number one, Otsuru and Jinno, another resident at the school came across the blooded road of child Afro's fight against a group of headband hunters, it is then after seeing the destroyed shrine on the side of the path that Otsuru notices the boy lodged inside the splintering ruin. Playful and naive, Otsuru takes it for a joke and says Afro is simply sleeping, unaware of the dire injuries he sustained prior. He was later rescued by Jinno and brought to the orphanage.
Through the passage of time, Otsuru grew up alongside Afro, Jinno, and the rest of the children at the kenjutsu orphanage, truly it was a life filled with laughs and happy times up until one fateful night. Word had gotten out about a legendary swordsman whom teaches the way of the sword and that he alone possess the Number One headband. That fateful rumor sparked a raging sea of blood that consumed all children of the orphanage and their cries echoed across the mountain tops. They live no longer as the raid on the school attracted scores of skilled killers, murders, and thieves all of which had no qualms about killing children, the surrounding field around the school had turned into a total war zone.
Blades and blood both drenched in pain stuck in the ground alike, Otsuru however was shot with multiples arrows in several fatal areas, each one coming out of the opposite side of its entry point.
The loss of blood signaled her death and Jinno, a man who has looked after Otsuru as if they we're flesh and blood marveled in agony at the sight before him, her lifeless body formed a figure of pain before death. Blue tears fell from his face and red streamed from his own injuries of battle and with one final questioning of Afro's lust for the revenge and the headband itself, he collapsed over the edge of the steep cliff from wince they were speaking only to fall into raging waters, taking Otsuru with him never to be seen again.
As an adult, Otsuru appears as a traditionally fair skin, young Japanese woman of a slim frame. Her black hair is in a long, thigh-length ponytail combined with side-swept bangs and a single lock of hair feathering her nose although in certain lighting, her hair appears purple. Tying it all together is a dark purple scrunchy accented by kanzashi as well as a one gold, 40mm hoop earring on both ears each. Otsuru's attire consists of a pink kimono and a unique violet Obi which splits into two knee-length sashes, her footwear is of a traditional tabi along with a pair of high-heel/geta hybrid.
Under her clothing is a long, giant scar, a reminder of the damaged she received as a child during the raid on the sword's school.
When she is introduced, she has once again found Afro in a near-death state (having been blown off a cliff by an RPG fired by Brother 6 and badly poisoned by an arrow in a fight with Soshun); she bandages him and takes him to her home to heal. She and Jinno survived the attack that was meant to claim the Number Two headband from Sword Master, and they were both saved by the Empty Seven.
Apparently, some time after the events at Sword Master's dojo, Otsuru became an agent working for Brother 1 of the Empty Seven Clan. She possesses the unique ability to siphon memories from people as they dream and used this ability to copy down Afro's sword style, which was used to complete the Afro Droid. Otsuru/Okiku was also supposed to kill him should the opportunity ever present itself, but she found herself unable to after having sex with him. She remarks that she still thinks of him as the same innocent boy she knew so long ago, revealing to him that she is actually Otsuru. Brother 2 of the Empty Seven then kills her for failing to carry out her mission and betraying the Empty Seven.
Otsuru apparently had a strong emotional effect on Afro as seen when in Episode five Afro calls out her name twice in his grief over the friends that he has lost.
She is a young woman who specializes in the art of healing, Otsuru is an excellent cook and adores fireworks.