Sachiko Yagami

"Don't be silly. I'm going to be with you all the way. No matter what…"

- Sachiko Yagami

Sachiko Yagami (夜神 幸子, Yagami Sachiko) is the wife of Soichiro Yagami and the mother of Light Yagami and Sayu Yagami who is oblivious to Light's ownership and use of the Death Note.

Appearance
Sachiko is a woman of medium height with straight chin-length brown hair that has bangs swept to the left side, small brown eyes and a slim build.

As a housewife, she dresses neatly but casually.

Character
Sachiko is a kind and caring woman who deeply loves her family where she worries about Soichiro Yagami's well-being while he works on the Kira case. When Soichiro is hospitalized due to a stress-related heart attack, she is frequently by his side to care for him. As concerned as she is about Soichiro, she also understands his convictions in working on the Kira case, and she stays by his side. Sachiko is proud of the academic success of her son, Light, and congratulates him on his good grades. When Sayu Yagami is wheelchair-ridden due to emotional trauma caused by her kidnapping, Sachiko aides her recovery, encouraging her and taking her for walks outside.

Plot
Sachiko is first seen waiting for Light to show her his exam grades. She is often at home when Light returns from school and is seen when the family eats or relaxes together. After the timeskip, she denies support for a match between Sayu Yagami and Touta Matsuda.

Sachiko is apparently never told that Light Yagami is Kira. It is likely that she was told that he died in the battle against Kira like his father Soichiro. Near makes sure that the truth of Kira's defeat is never publicized, and in the manga, people simply believe Kira is resting.

Film series
Sachiko's role in the film series is essentially the same as her role in the manga.

After Light is exposed as Kira and is killed by Ryuk, Soichiro never reveals the truth behind their son's death. He tells Sachiko and their daughter Sayu that Light was killed by Kira instead. The year after Light's death, at the end of the second film, Sachiko and Sayu make Light a birthday cake.

Ten years later, Light's identity as Kira is publicly exposed by Yuki Shien during the events of Death Note: Light Up the NEW World. Her response to this revelation is never shown in the film.

Drama
Sachiko dies from a terminal illness prior to the events of television drama, but she is shown in several flashbacks throughout the series. Her death strains Light's relationship with Soichiro due to the latter being unable to be present at her deathbed.

In one flashback, Light fondly remembers pretending to be a police officer while his mother happily watched him and his sister play.

Netflix film
Light's mother is unnamed in Netflix's 2017 Death Note film. Similar to the drama, Light's mother passed away before the events of the film. She was killed when Antony Skomal hit her with his car. In an act of revenge, Light kills Skomal, making him Light's second Death Note victim.

Light's father James Turner describes her as being sort of a hippy and that she said, "Karma's a bitch."

James later talks to Light and Mia Sutton about her as well, saying that she wouldn't have been caught within ten miles of him in high school, but their conversation is interrupted by L.

Conception
Takeshi Obata said that he had no real concept behind the design of Sachiko; he claimed that he encountered difficulty in drawing female characters who were not the main characters. Tsugumi Ohba did not include Sachiko in the final chapter of the manga but stated that someone in the Task Force would likely tell her that Light Yagami and Soichiro Yagami died in order to stop Kira as the Task Force members would never let the world know the truth about the Death Note and the Kira case.

Etymology
Sachiko Yagami Sachiko Yagami Sachiko Yagami Sachiko Yagami
 * The name Sachiko means "happiness, good luck" (幸) (sachi) and "child" (子) (ko).
 * Sachiko's surname Yagami means "night" (夜) (ya) and "god" (神) (kami/gami).