Sayonika Nayomi is a supporting character in GhoulGirls90's Fanon, the main protagonist of the game's sequel, Yandere Simulator: SNAP Mode 2, a minor character in Yandere Simulator: SNAP Mode 3 and one of the three deuteragonists in its Nightmare Mode. She is currently one of the students that attend Akademi High School. She is the president of the Literature Club.
A cheerful and smart girl who is the president of the Literature Club. She is incapable to defend herself from any physical fights that make other students think she's coward.
Sayonika is a very cheerful, bright and sweet girl. While she's smart and intelligent, she is very afraid and incapable of defending herself such as if she got into physical fights because she's very not brave enough. She would desperately beg for mercy when someone threatens to hurt her.
Sayonika has the Social Coward Persona. If a camera is aimed at her, she will strike a cute pose nervously. As one of Simon's friends, if she witnesses murder, she will run to Simon and tell him about what Ayano did and then he will proceed to apprehend her. If she sees a corpse, she will run to near Simon and call the police. She cannot participate any physical confrontation against murderers.
Sayonika is friends and in good terms with Yuri.
In Yandere Simulator: SNAP Mode 2, due to being absent in a day where Yuri gets unexpectedly removed from her club, Sayonika began to fear her after seeing sudden strange behavior and became insane, psychopathic and murderous. She couldn't understand why she wasn't being herself. She is unaware that Natsuki kicked Yuri out of her club.
If Sayonika finds a note about what happened with Yuri that reveals it has something to do with her substitute, she may confront Natsuki.
- She is based on femslash ship between Sayori and Monika from the Doki Doki Literature Club game.