|Appearance||Extra Class: Black Cat Saya|
Saya is a small black kitten with the ability to shape shift. As such, she is shown taking the appearance of Ayako and her mother during the story. She retains Ayako's appearance as she ages into an adult, and as a woman she is shown having short curly hair and wore teaching attire. At times when shape-shifted, her eyes and teeth change to reflect those of a cats.
Saya is cruel and manipulative, switching between kind and friendly one minute and cold and violent the next. As a cat she is unable to ignore her normal instincts and even when in the form of someone else could be seen scratching things and couldn't handle hot drinks. She had a very deep rooted grudge against Ayako, but it appeared to spread to other humans.
Saya's original body had been hit by Ayako's family while on the way home from celebrating the New Years with relatives. She laid there until a month later, when she gained the new form of a young kitten that was abandoned in a box found by Ayako, and then adopted by her family. In this time she behaved like a normal cat and appeared to be friendly and sweet. But once she found the perfect moment to strike she waited until the following day when she could transform into Ayako's mother.
After Ayako was convinced her parents had left, she was shocked to find her mother still home. She explained how she decided to stay behind out of concern for Ayako and called Yamada to let her know she was no longer needed. She showed no remorse after Ayako panicked, finding Saya's discarded collar and suggested Ayako sit down for breakfast, but after Ayako offered her the freshly made hot coffee, Saya tossed the container to the floor and insulted her. As Ayako stood in shock, she went on to say she should get ready for school and that she made her lunch; stuffed with her own cat fur.
That night, after she thought Ayako went to bed she prepared to claw everything she could get her hands on, still as Ayako's mother, and destroyed their living room. Ayako caught this going on and spied on her until she seemed to notice, then she headed up stairs to go to bed. The next morning she caught Ayako trying to tell Yamada what was going on and in response, she grabbed her and threw her to the floor before shutting the door on their neighbor and suggesting Ayako go have breakfast. She watched as Ayako frantically tried to call her parents, revealing she cut the phone line before slowly beginning to regain her cats eyes and mouth, asking her why she abandoned her on the road that night to die. Ayako runs away in terror and she chased after her until she was suddenly hit by an oncoming car. She made Ayako experience the very pain she felt that night before killing her.
Later, Ayako awakened in the hospital to find her parents, who explained that they came home and found her unconsciousness. They had tried to call her but were unable to, and when they tried to talk to Yamada she acted strangely around her. They are relieved Ayako is okay, and after she reveals Saya was dead they decided to buy her a pet hamster to make her feel better. In this time, it is revealed that Ayako is actually Saya, and she had been burying Ayako in the grave set up for her in their backyard.
Three young school girls are observing Ayako's old home when they reveal that her parents vanished twenty years ago. However Ayako had lived, and by now she was an adult. As they wandered around a little they found a picture of Ayako standing with her parents- and its in this instance one girl sees Saya's face, not Ayako's.
They were soon caught by an unhappy "Ayako-sensei", unaware of her actually being Saya as they walk away. She reminds them that they had been warned to stay away from this home and now hungry, the girls begin to chat about lunch when they ask her what she's in the mood for. Her response implies she killed and ate Ayako's parents.