A high school senior and president of the school’s kendo club, she is extremely skilled with a bokken and close combat. Calm and collected with a sense of pride in her skills and those that she’s with, Saeko is among the most reliable of the group. Everyone can count on her combat skills to pull them through a tough spot if need be. Not much is known about her family except for her father who had traveled abroad on a self-defense conference before the advent of the Outbreak. She has shown fondness towards Takashi and believes in his abilities to get them through the crisis.
Four years prior to the story, Saeko was attacked by a man on her way home one night; however, she was able to easily overpower the man since she had her wooden sword with her. After severely injuring the man, the police released her due to the circumstances, but the events of that night left Saeko with a profound revelation. She discovered a sadistic side to herself that enjoyed inflicting pain and suffering. It is also implied that at some point in the past she had liked a boy. But she was never able to tell him how she felt, feeling that her dark side meant that she did not deserve to confess her feelings..