|“||Our friendship will last forever.. It will never die...||”|
—Sayaka Ooue, Corpse Party: Book of Shadows (Episode #4; 『Purgatory』)
Sayaka Ooue (大上 さやか Ōue Sayaka ) is a student from Paulownia Academy's high school class 2-1, and a victim trapped inside Heavenly Host Elementary School. She was brought to Heavenly Host by her friend Naho Saenoki to look for Kou Kibiki.
Sayaka is a teenage girl of somewhat above average height and below average weight. She has blue-green eyes and long curly brown hair, with three green hair clips on the left side of her head. Like the other female students of Paulownia Academy, she wears a byzantium purple blazer with a white shirt underneath, a plain red necktie, and a dark blue skirt with white lace. She also wears black thigh high stockings and brown loafers. She has a beauty mark just below her right cheek.
Sayaka is a sweet and caring girl, albeit leads a busy life, especially because of her part-time job as a radio personality. Her friendship with Naho is strong, forgiving her if she does anything wrong. She would even risk her life for Naho's wishes, even when in death. She sees Kou as handsome but is not romantically interested in him. She dislikes maggots and the sight of blood; the sheer sight and feeling will send chills down her spine.
Sayaka also declines and possibly hates her childhood friend Haruyuki Inumaru as she gets annoyed by his behavior.
Sayaka used to be an unpopular and unattractive girl. However, she got sick of herself, so she forced herself to be prettier to increase her popularity and self-esteem. It's also the reason she is surprised when she finds out that her beautiful friend has no social contacts, as she expected that every pretty girl must be popular.
- In Corpse Party (PSP, iOS), Sayaka's name tag states that she died of darkening while searching for Naho. But in Corpse Party: Book of Shadows her fate is left in the hands of Yoshikazu Yanagihori and his sledgehammer.
- Although she has diabetic chocolate, Sayaka was shown to eat several sugary foods in EX CHAPTER 04 『Memories, Like Beautiful Dreams』 and nothing about her diabetes was mentioned.