|Voice||Dawn M. Bennett|
Once she is fully implemented, the player will need to sneak past her to access the tranquilizer and the syringe. YandereDev has stated that certain medicines will be kept in a locked container hiding somewhere in the office in the future. It can only be opened with a key, which the nurse will hide in a different spot each week.
She has fair skin, light pink hair, and amethyst colored eyes. She wears a short-sleeved white nurse uniform with a low collar and a nurse's cap. She also wears light pink stockings with a white garter belt and white flat heels.
"Muja is a young nurse who desires nothing more than to take care of other people...although she usually ends up causing more problems than she solves due to her air-headed, clumsy nature.
Muja will be serving as a substitute for the school's usual nurse, who isn't available during the sixth week of gameplay. She will become fond of Senpai very quickly, during a point in time when he definitely needs someone taking care of his health.
Her intelligence is not her strong point, but she is a very sweet and caring person, and it's very easy to see how any schoolboy might develop a crush on her - including Senpai..."
Muja is meant to be pure and innocent. She is probably the only Faculty member who is incapable of self-defense. She is expected by the other Faculty members to act well-trained and brave. However, she does not fit for that kind of person due to her clumsy personality. She is somewhat shy and awkward. She does not have a crush on Senpai, but she views him as a very, very close and warm friend. In the future, Senpai will probably have a crush on her.
Muja's default reputation is -3.
Though it is currently unknown, YandereDev has said that Muja's routine will put her in close proximity to Senpai and other people, including students and staff. It is presumed that her routine will be similar to the regular nurse, but nothing is confirmed.
The topics towards Muja Kina is Negative/Neutral/Positive follows:
- Martial Arts
- Everything else.
In the final game, Senpai will become sick for the one week while Muja Kina is at the school, substituting for Nasu Kankoshi. He will visit her once per day. Senpai, on that note, is attracted to sexually attractive nurses, so their relationship might grow as a result of these interactions.
If she entered a relationship with Senpai, he will most likely pursue a career in the healthcare industry.
- Muja will disappear when her week is over, even if she is eliminated peacefully.
- YandereDev has stated that the substitute nurse is not a rival who can catch a knife.
- In the final game, when a student is poisoned or drowned, witnesses might run for her instead of the teachers.
- Her name is derived from "無邪気" (mujaki) which translates to "innocent" and "simple minded". "な" (na) is an adjective-modifier.
- YandereDev has considered the idea of Muja attending Akademi when she was younger, and always having the fantasy of confessing her love under the cherry tree, but never finding the right person. She would compensate for this in a childish manner by confessing to Senpai under the cherry tree at 5 like the legend requires. 
- She won't have a reputation stat, but will instead have a 'job performance' stat, which will be lowered in ways other than gossip.
- YandereDev does not believe she is acquainted or in any way related to Mida Rana.
- YandereDev has stated that she may be the only faculty member who does not have self-defense training.
- Muja's reaction to murder would be to warn others in the Faculty Room, but she may go the wrong way at first.
- If she used pepper spray, she'd spray herself by accident.
- Her favorite food is Cotton Candy.
|“||Oh, my! Your face is turning red! Do you have a fever?! Come see me any time! I'm always happy to take care of you...||”|
— Muja in "Yandere Simulator Rival Introduction Video" 
|“||Oh, my! Your heart is beating so fast! Are you getting sick? I'll always be there for you Senpai. I'd be happy to take care of you for the rest of your life.||”|
— Alternate Muja line for the "Rival Introduction Video".
|“||I don't know what you're trying to do, but if it's supposed to be a joke, it's not funny.||”|
— Muja when Ayano failed to steal her keys.
|“||EEK! WATCH OUT! ...owwwww...I'm sorry, I got you right on the head, didn't I? Here, let me see...oh, no! I gave you a bruise! I'm so sorry! Sorrysorrysorrysorrysorry! ...huh? What's this flower doing on the ground?||”|
— Hypothetical dialogue of Muja reacting to someone giving her a flower.