Yagami Sayu

Japanese name:

夜神 幸子

Light's younger sister. She never learns of Light's possession of the Death Note or his identity as Kira.

SpoilerIn the second story arc of both the manga and anime, Mello's gang kidnaps her in exchange for the Death Note possessed by the investigation team. Although being returned unharmed, Sayu falls into a state of shock, eventually becoming unresponsive to the presence of others.

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