|Family and Relations|| Gennosuke Yumi (Father),
Shiro Yumi (Younger Brother)
|First Appearance||Z Mazinger chapter 1|
During her childhood, Sayaka met Koji Kabuto and they became friends. They even went to the same high school.
Sayaka has the same appearance as her original counterpart, but as shown in the cover art her hair is black instead of the usual brown.
Sayaka, much like her original counterpart is tomboyish with a strong will. She also has feelings for Koji despite almost always arguing with him; worrying about him when he is danger and was distraught when she was forced to fight him for Ares's entertainment. Sayaka also had a great respect for Aphrodite when she stuck up for them and piloted her as Aphrodite A in her honor.
While Sayaka has not had the same amount of training as Koji, she can at least give him a run for his money whenever given the time after receiving training from Toko Kabuto. She also became great enough to effectively pilot a robot like Aphrodite A after inheriting her spirit.
Sayaka went to visit her father at a research site for mysterious ruins with Koji. Suddenly an earthquake occurred and Koji fell down into the ruins. Sayaka was worried sick about Koji, especially when some people said he was dead. When a Mechanical Beast attacked and Zeus appeared with Koji inside, Sayaka was more than relieved that Koji was alive.
As the Olympus army kept attacking, Sayaka never stopped thinking about Koji and went to train with his mother. She was then kidnapped by Ares to lure Koji into a trap. The trap was having a brainwashed Sayaka fight Koji, something he was reluctant to do. Aphrodite appeared and removed the brainwashing from Sayaka but Ares attacked and mortally wounded her. Aphrodite then asked Sayaka to pilot her body much like how Zeus gave Koji his body to pilot, to which she accepted. HSF had her remodeled into Aphrodite A and Sayaka became the pilot. Despite Koji objecting to Sayaka getting in danger, Sayaka stayed by his side.
As Z Mazinger and Aphrodite A stormed the fortress of the Mechanical Gods, Sayaka is forced to fight Aphrodite's old rival Artemis. She manages to defeat the Mechanical God in time to help Z Mazinger fight the Cerberus Mechanical Beast. Impressed with Sayaka, Artemis shoots an arrow from her tank to have the Cerberus attack Dr. Hell. However, even after the Cerberus and the rest of the Mechanical Beasts were destroyed, Hades unleashed his army upon the surface. Koji asked if she and Aphrodite A were willing to stay and help, to which she agreed.