Masako Nori is an OC created by Kriemhild von Schwarzwald. She is a 2nd year student at Akademi High School who much the dismay of her classmates is a social justice warrior.
On the surface, Masako is a smart and caring girl who acts compassionate towards people regardless who they are. However she has a habit of going on long, uber-politically correct rants on her blog and sometimes in person if one triggers her, with the latter earning her the nickname of "Social Justice-chan" or simply "SJ-chan". And that's only what she shows those around her, as she even goes as far as to anonymously bully those that she sees as offensive. For example, she'll sometimes leave death threats in male students' lockers if she find evidence of having panty shots or other perverted material. And if Senpai is a female, she'll act even more like a stereotypical Tumblr feminist and despise men entirely.
- Senpai: She sees him as the perfect boyfriend due to having no "patriarchal" tendencies or perversions. And in the case of the female Senpai, it's due to agreeing with some of her views.
- Info-chan: Masako absolutely despises Info-chan due to taking panty shots of other girls without consent and supporting the "patriarchy" by selling them to boys. This isn't helped by the fact that she was blackmailed by her on a couple of occasions. She even speculated that she was a actually a guy before hearing her real voice. Despite this, Info-chan only views her as a mild annoyance and only threatened her due to scaring off her customers.
- Ayano Aishi: Their relationship depends on Ayano's actions. For example, she'll grow to hate her if she catches her taking a panty shot and suspect that she's working for Info-chan even after apologizing.
- She was inspired by a Tumblr user who accused Yandere Simulator of being racist, sexist, and ableist; even telling the fanbase to kill themselves. To be more specific, when YandereDev shared the original post on Twitter a fan suggested there be a rival based on the user in question
- Her actions were also inspired by several people who harassed a Steven Universe fan artist named Zammi070 to point where she attempted suicide.
- A similar character will appear in an upcoming CloudNovel game by the same creator and has no interest in her appearing in the real Yandere Simulator.