Yamaoka (山岡 Yamaoka) is a character from the one-shot Dead Man's Questions.
Yamaoka lived together with a wanted man responsible for a child murder case 15 years ago. Probably in a attempt to hide him, she was careful about who entered her house. Yoshikage Kira, assigned to kill the man, tried to trick her into believing he was a man delivering a plastic model to open the door, as Kira needed permission to enter the house. She didn't want to open the door and made constant questions about his delivery, until he finally convinced her to open the box mail for him to give her the formulary. She opened it and Kira entered the house, engaging in a confrontation with Rocky soon after. She saw the knife Kira dropped and became worried that someone else might have been inside the house, as Rocky was constantly barking.
After Kira stabs the wanted man he calls her with a phone, telling her to call the police. She asks if the man is calling her inside of his own room, while Kira wonders if she was deceived by wanted man or knew about his past all along.