Kumi Demura
Student Info
Role Student,
Protagonist (Kuudere Simulator)
Class 1-1
Club No Club
Persona Loner
Crush None
Strength Incapable
Appears Week 1 (Debug)
Games Kuudere Simulator
Kuudere Simulator 2
Kuudere Simulator 3
Voice Kendra Braun
(I Want My Senpai Back)
Michaela Laws
(Kuudere Simulator)
Kuudere-chan, whose real name is Kumi Demura, is the protagonist of Kuudere Simulator, Kuudere Simulator 2, Kuudere Simulator 3, and a female student who currently attends Akademi High School. She is the fourth student to be introduced as an Easter Egg.

She appears in the Kuudere Simulator spin-off games and in the "I Want My Senpai Back" video.[1] Her name was stated as Kuudere-chan in the description.

In the Kuudere Simulator games, she sits on a wooden chair in the middle of an empty room and does not move. The player can scroll the mouse around to get a better view of her.

As of the November 15th, 2015 Build, Kuudere-chan was added into Yandere Simulator as a student with the name Kuu Dere whose real name is now Kumi Demura as of the July 1st, 2020 build.


Kuu has short, azure blue hair and red eyes that are another colored version of those of Osana Najimi (as of the August 3rd, 2019 Build. She wears the default female school uniform unless customized by the player and knee high white socks. She has the same skin tone as Ayano. Her bust size is 1.

As of the March 31st, 2018 Build, the edges of her hair were more defined with dark blue, but as of the April 26th, 2018, that was no longer the case, and her hair was colored dark aqua. Her hair is derived from Honoka Futaba, a character that can be bought in the Unity3D Asset Store.[2]

In Kuudere Simulator, her hair is more oval-shaped and is longer.



"The school librarian. \ Strongly prefers solitude. \ Very rarely expresses emotions."



Kuu hiding her face.

She is a kuudere. A kuudere is a common personality trope in anime that displays cold-hearted and inexpressive behavior, as they have difficulty recognizing their feelings (Kuu). They only occasionally show their hidden caring and nice side (Dere).

She very rarely expresses emotions and prefers solitude, according to her Student Profile.

Among the personas currently implemented in the game, Kuu is a loner. If she sees a corpse or witnesses a murder, she will run home and call the police. She cannot participate in physical fights against murderers. Due to her having the Loner persona, she will hide her face if Ayano aims her phone at her.

It's possible that, in the future, she will have a unique reaction to murder. This, however, is programming a special case that applies only to her and Robot-chan, and will be difficult from the programming side.[3] This persona may be called "Apathetic".[4]



Kuu's reputation graph.

Kuu's default reputation is +3.

Liked: 0

Respected: 10

Feared: 0



Kuu reading a book at the table on the left side of the library. May 18th, 2018.

At 7:00 AM, Kuu enters the school grounds, walks to her locker and changes from her outdoor shoes to her indoor shoes. As of the July 18th, 2017 Build, Kuu will walk to the library after changing her shoes. She will then sit at the table on the left side and read a book.

At 8:00 AM, Kuu walks into Classroom 1-1, sits at her desk, and plays around on her phone before her classes start. She starts her morning classes at 8:30 AM, and leaves to go eat lunch on the rooftop at 1:00 PM.

Kuu walks to class again at 1:22 PM, sits at her desk, and plays around on her phone again until her next classes start. Her next classes start at 1:30 PM. At 3:30 PM, she participates in cleaning time which ends at 4:00 PM. Afterwards, she heads to her locker and changes from her indoor shoes to her outdoor shoes and will walk home after that.


The topics towards Kuu are (Negative/Positive/Neutral) as follows:


  • Drama
  • Music
  • Martial Arts
  • Memes
  • Friends


  • Video Games
  • Anime
  • Violence
  • Reading
  • Solitude


  • Everything else.


  • There was once a bug in the January 15th, 2016 Build where Kuu Dere had Mai Waifu's profile. This was later fixed in the February 1st, 2016 Build.
  • YandereDev likes the idea of her repeating her quotes from Kuudere Simulator; however, this would require a lot of "special case" code.[5]
  • She was implemented into Yandere Simulator in the November 15th, 2015 Build.
  • Pressing E while playing Kuudere Simulator will give her an eyepatch. Pressing T will turn her into Tsundere-chan. Pressing H in Kuudere Simulator 2 will turn her into Himedere-chan.
  • All of her dialogue in Kuudere Simulator, Kuudere Simulator 2, and Kuudere Simulator 3 appears as blue text.
  • In older builds, her Student Profile used to say that she had not been witnessed exhibiting emotions. However, she would show fear when she witnessed murder.
  • In her cameo in "I Want My Senpai Back", she has brown eyes instead of red.
  • Kuu's appearance is a reference to Rei Ayanami from Neon Genesis Evangelion.[6]
  • Kuu makes a small cameo in the gaming club by appearing on the dating simulator game screen.
  • The reason why she was moved to another spot on the rooftop is because during lunchtime, the Basu sisters both eat their lunch.
  • As of the July 18th, 2017 Build, Kuu is the school librarian.
  • If YandereDev decides to have student nicknames, then her real name would not be Kuu Dere and this would instead be a nickname given to her, due to her emotionless and apathetic nature.[7] He suggested "Kumiko Deremoto" as a hypothetical name for her.[8]
  • She has a similar personality to Ayano Aishi, Homu Kurusu, and Geiju Tsuka.


I don't even need a senpai.
— Kuudere-chan in Kuudere Simulator.
Who wants a senpai anyway?
— Kuudere-chan in Kuudere Simulator.
I don't care who senpai is dating.
— Kuudere-chan in Kuudere Simulator.
Senpai can do whatever he wants.
— Kuudere-chan in Kuudere Simulator.
A senpai would only make my life more complicated.
— Kuudere-chan in Kuudere Simulator.
I don't really care.
— Kuudere-chan in Kuudere Simulator 2.
— Kuudere-chan in Kuudere Simulator 2.
It's ok, I guess.
— Kuudere-chan in Kuudere Simulator 2.
It doesn't make any difference.
— Kuudere-chan in Kuudere Simulator 2.
I don't see the point.
— Kuudere-chan in Kuudere Simulator 2.
Senpai is safe now. Or something. I guess.
— Kuudere-chan in Kuudere Simulator 3.
She deserved it.
— Kuudere-chan in Kuudere Simulator 3.
Good riddance.
— Kuudere-chan in Kuudere Simulator 3.
That was loud.
— Kuudere-chan in Kuudere Simulator 3.
What a mess.
— Kuudere-chan in Kuudere Simulator 3.
No, I haven't seen any Senpais around here.
— Kuudere-chan in "I Want My Senpai Back".
The Library is such a soothing place to sit and relax and enjoy a good book.
— Kuu commenting on the school's website.




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