Mother: Kei Yuki *Biological*; Kikiro Karasu *adopted*
Yumiko is the daughter of Akatsuki's Hidan and Kei of the Yuki clan. She posseses the kekkei genkai for Ice Release but it is not discovered until she manages to perform a low level ice release jutsu after she makes another member of the Yuki clan teacher it to her, though he was unwilling to do so he gave in once Yumiko decided she would not stop bothering him. She is currently in Amegakure with Aiko (the adopted child of Konan), her adopted mother Kikiro Karasu, and a Jashinist named Haru who is teacher Yumiko about her Yuki blood line.
Before slaughtering his neighbors and leaving Yugakure Hidan had lover named Kei (A member of the Yuki clan that left the land of water and tried to live a peaceful life without revealing her blood line). The night Hidan slaughtered his neighbors he murdered Kei and decided to take Yumiko with him, his reason was so he could raise her to be his idea of a true shinobi. When Hidan joined the cult-like faith Jashinism he had Yumiko converted and left her behind with the other Jahsinists once he had achieved immortality, believing she would be raised to be violent and merciless, though Hidan was wrong and Yumiko was modeled after a younger Jashinist named Haru who tried to teach Yumiko to be faithful to her religion, but also to be more compassionate than her father, she isn't immortal and can't inflict pain like Hidan so it would be best if she doesn't act as violently as him. Shortly after joining Akatsuki Hidan returned to the temple, after learning Yumiko wasn’t growing up the way he wanted her to Hidan decided to bring Yumiko with him back to Amegakure where she remained for the duration of Akatsuki's downfall. After Konan died Yumiko was only left with her adopted mother Kikiro and Konan's adopted daughter Aiko, she is clingy with Kikiro and does not like to be away from her,she is the same way with the Hidden Rain's stand in kage Aiko but to a lesser extent.
Yumiko is currently living with Kikiro (who defected from Akatsuki with Konan) in Amegakure learning of her Yuki blood line with fellow Jashinist and Yuki clansman Haru.
Yumiko a happy clingy child and is loyal to those she cares for, but she can also be incredibly violent; much like her father. She is usually seen with a smile on her face following Hidan and Kikiro around the Hidden Rain. Yumiko, like Hidan, can be rather rude at times and has a foul mouth but unlike her father Yumiko is willing to show respect to the Akatsuki members and refers to all of them (With the exception of Aiko) as "sama" whether she is trying to speak directly to them or is speaking to someone else about them. When Yumiko turns violent she refuses to give up the fight unless she can kill whoever enraged her, though she has yet to kill anyone since she is usually pulled away from situations where she turns violent. Yumiko has an obsession with dango, she will do anything for dango, Hidan often makes Yumiko behave by telling her he'll take away her dango if she doesn't do as he says.
Yumiko likes to play and has a love of dogs, she even has a puppy suit she likes to wear and pretend to be a puppy. Often when she has her puppy suit Yumiko goes up to Kakuzu saying how she'll make "the monies" for him with her suit, she goes ignored but often goes off on her own to make "the monies".
She also has great disdain for the Hidden Leaf and the people within it, she's even gone so far as to confront Naruto and tell him she will kill him when she gets older. She had even attempted to lash out at Shikamaru when she learned that he was the one who was responsible for Hidan's "death". After the complete destruction of Akatsuki Yumiko becomes overly attached to Kikiro and refuses to leave the woman's side, even following her outside of the village just to reassure herself that nothing will happen to her adopted mother.
Yumiko is an around cute, happy little girl with a love of dogs, dango, and playing pretend. Kikiro often calls Yumiko puppy like because of her undying loyalty to her father, adopted mother, religion, and friends; even at such a young age she would never leave those she cared about alone when they were feeling down and was protective of them, even when she met Tsunade Yumiko threatened to kill her if anything were to happen to Aiko (Konan's adopted child and stand in kage of the Hidden Rain) even though Yumiko would be unable to do anything due to her young age and lack of power. She is also considered puppy like because of her often playful nature and seemingly endless energy.
Yumiko is small for her age. She has long, messy silver hair that covers the left half of her face, two long "stupid hairs" on the top of her head and her father's purple eyes; she wears a floor length white kimono with a red tomoeri and obi. Under her kimono Yumiko wears a long black dress. She often wears her Jashin pendent around her neck. Yumiko also appears to be missing her right canine, her tooth having come loose and fallen out naturally.
Every now and again Yumiko can be seen carrying a rather large blade, it was given to her by Hidan and is made from a very light and very sharp material. Yumiko likes to carry her blade whenever she goes to the Leaf village or Leaf ninja come the Amegakure to see Aiko, the blade makes Yumiko feel fearsome like the Akatsuki members.
Because of her mother Yuki bloodline, Yumiko inherited the kekkei genkai for ice release, she realizes her Yuki blood when she manages to used an ice release jutsu taught to her by another Yuki clansman, a Jashinist named Haru (he decided to show her how to perform the jutsu believing that she would be unable to do it and give up on trying to learn ice release jutsu). Once Kikiro, Aiko and Haru pick up on Yumiko's Yuki blood they begin training her to use her kekkei genkai, she goes through simple training because of her age and at this point just learns of her bloodline and how she can use the ice release.
None really, Yumiko is a very small, slow child. She often hides behind things and waits for a target to approach then slices their leg, if she can, and runs. Often times when faced with danger Yumiko will talk big but will flee when the danger become real, often running to Hidan or Kikiro for protection. The only time Yumiko actually turns violent is when she is faced with someone around her size or age.
Yumiko was just a small 3 year old. She had been brought to the rain village by Hidan and was adjusting to her new life. She often hung out with Aiko, either annoying the teen or sitting quietly; it depended on her mood. Yumiko was clinging to her father and beginning to believe that the Akatsuki member Kikiro Karasu was her biological mother.
Just before the start of Shippuden Hidan and Kakuzu go out on a mission to capture a jinchuriki, unknowingly, with Yumiko following them, neither of them realizing it until they are too far along their journey to just carry her back. When they encounter the target Yumiko becomes nothing short of a distraction for her father and gets in the way while she she tries to run to Hidan for comfort, her chasing after him puts her in danger and when Hidan becomes a target for attacks Yumiko's life is on the line and in her father's hands forcing Hidan to make a choice as the jinchuriki prepares to strike, attack the target and leave his child behind defenseless against the oncoming attack or grab Yumiko and get out out of the line of fire. Hidan chose to save his daughter and when the dust from the jinchuriki's attack settled it had already escaped causing the mission to end in failure.
Yumiko is still on the side lines in Amegakure with Aiko and Kikiro, but she is beginning to leave the village more and explore the outside world little by little.
She is kept in the dark about the deaths of Akatsuki members but becomes aware of Hidan's death when he does not return to the Hidden rain. She developed a hatred of the leaf village for killing the Akatsuki and tells Aiko and Kikiro she will avenge the deaths of the Akatsuki members.
During the current war Yumiko is living in Amegakure with Kikiro learning of her Yuki heritage and the Ice Release.