Chiyuki

The Black-Haired Woman (黒髪の女 Kurokami no Onna) often referred to as Onna, is an amnesiac woman taken in by Nona to Quindecim and hires her as Decim's assistant. Later, her real name is revealed to be Chiyuki (知幸 Chiyuki).

Appearance
Chiyuki is a young woman with violet eyes. She has shoulder-length black hair with a streak of white in her bangs. Her slender and semi petite figure is accentuated with a black crop top, a mini skirt held by a white belt, and ankle strap heels. She accessorizes with a necklace and a white bracelet.

Personality
Chiyuki appeared innocent but skeptikal when she first woke up. However, after she became accustomed to living in Quindecim, she acted as a strong-minded individual who always says what is on her mind whenever she feels it's necessary. She does not hesitate to oppose Decim if she feels there is something wrong in what he says. Also, because she retains her humanity even when all her memories are lost, she can give valuable insights to Decim whenever he is judging.

History
When Chiyuki was young, she liked reading Chavvot with her mother –a story about a boy named Jimmy who falls in love with a deaf girl named Chavvot. She has stated that the moments when Chavvot smiles are her favorite parts.

After her death, Chiyuki became one of Decim's customers. However, unlike the other humans who had no memories when they arrived, hers were intact and she was aware of the fact that she was dead. For this reason, Decim could not provoke her into playing a Death Game and with Nona's permission, he had her memories erased and extended her judgement period. After that, she was allowed to stay in Quindecim and assist Decim in arbitrating.

Death Billiards
In Death Billiards, she was simply referred to as the 'The Black Haired Woman' who quietly sits back and observes a judgement game as Decim's assistant.

Death Parade
Her role is further elaborated on in Death Parade: Because she was aware of her death, Decim couldn't judge her. With Nona's permission, her memories were erased and she was assigned the role of Decim's assistant as part of her judgement. She helps Decim understand human emotions and provides insight in passing judgements and reading people's feelings. Despite this, she disapproves of the concept of bringing the darkness out in people's hearts, as she feels the arbiters are creating them instead. Eventually, she began to remember who she was, largely due to her re-reading Chavvot, an old favorite book. As she begins to remember, her body begins to crumble, because humans are not permitted to stay in Quindecim for too long before they are judged.

Decim
The two have a close relationship. She helps teach Decim about humans and understanding their emotions and actions.

Nona
She is Decim's boss and by extension, Chiyuki's. Nona assigned her to Decim as an assistant and while the two have not interacted since episode 2, the former believes she has a somewhat good understanding of humanity but still has much to learn.

Mother
Her mother frequently shows up in her memories and the two seemed to have a strong bond.

Trivia

 * It seems the picture book, 'Chavvot' and ice skates play a big part in Chiyuki's identity, though it has yet to be revealed how.
 * She appears to be a decent cook, as seen in episode 7.
 * She has a closet filled with spares of the outfit she wears when assisting at Quindecim.