|Alternate Names||The Evil Behavior (By Mizuki)|
|First Apperance||Chapter 72|
"Haha... Said it whatever you want. Using the mans as my puppet and a weapon is my lifestyle. However, the only man that I can't catch with... is Zui-sama. Yuuma Mukai has killed Zui-sama! Yuuma Mukai is the one who used those dirty move first...... so I will never forgive him! No matter how you people said it, everyone in the classroom was believed Mukai is the Chairman Marble...! Whatever, he's only have 20 minutes of life span left now."
– Karin Koma after revealed her real purpose, Chapter 165
Karin Koma (小間 カリン, Koma Karin) is a character introduced in third part of the story. Karin is one of the antagonists in third part of the story.
Karin lived with her mother since childhood, her mother keep bring numerous different man into their house and the man was acts as Karin's father. One day, Karin has received an new father and their family is having a really good relationship. However, a few days later, Karin's new father killed her mother in her house, due to her father love Karin a lot more than her mother did. When Karin is about to be rape by her father, she stopped her father by attack his head with using vase. Soon the polices come to Karin's house and catches her father to sent to the jail.
After Karin's father was sent to the jail, Karin was happy and thanking the God to giving her such a beautiful face. Since that time, Karin has keep playing a lot of mans as her puppet with non-stop. Karin has be never happy about it.
Chapter 71-185 (Third Season)Edit
Karin first appeared at Chapter 72, Karin is chosen as one of the 30 players to be play at Real Account Tower.
After the first game is finished, along with the rest of the players was having a bath.
During 24 Hours Unscrupulous Hunting Campaign game, Karin is tagged with Zui Zakuro. When Zui using his power to a person, Karin find this to be amazing and think this power can be only explains as a "supernatural power". Right after Zui announced he wants to challenge Yuuma in the next day, Karin was thinking of having Zui become one of her puppet too. Though Zui reads Karin's mind with his power, he stated that all Karin actually wants is not playing the mans' feeling but having revenge on her father for her long-deceased mother. Karin surprised it and finally understand what she want, she want to having her new journey on having revenge on her father, but Zui stated her wish will never happen as her father already killed himself in the jail since the Real Account Tower event is started. Karin feel disappointing and sad because she will never have any wish to be grained, though Zui said he can helps her if she joins his group, known as the "Noah Wave". Karin accepts the invite to joins Zui's group and she started to fell in love with Zui.
During Zui fight against Yuuma, Karin and Zui's other teammate was watching the match. When Zui can't holds on anymore, Karin tried to asked Suzuri and the others to helps him but they don't want due to they didn't want to losing their points. After Zui is defeated, along with the rest of the players who was in the factory was having their points steals by Hako and Aiji Hoshina. After everyone is left the area, Karin revealed her true purpose that she wants to obtains Zui's power. Though Zui soon noticed that Karin doesn't want to kill him, he told her that she must kill him in order to obtains the power of the God and believed she can become a better God than he does. After hearing Zui's words, Karin finally killed him and obtained the power of the God.One day after the fourth game finished, the fifth game is started with every players wears school uniforms. After Karin revealed she obtained the Mortal's Smartphone to the other players, she said she can uses the prediction ability to see if Yuuma is the Chairman Marble or not. After used the prediction ability, it's revealed Yuuma is indeed the Chairman Marble, Karin run away and voted Yuuma afterward. After Airi Homura's death, Karin goes to the toilet and having a "special massage" in order to retain her beauty, though it's seen by Ayame Kamijou which make Karin so embarrassing. After Ayame gives Karin an another "special massage", Karin follow Ayame's request to use the prediction ability once again to confirms Yuuma's state, thought it's still stated he is the Chairman Marble. Then, Karin got angry and said she must vote him again in the next turn. During Ayame's conversation with everyone about whatever Yuuma is the Chairman Marble or not, Karin requested Yasuharu Tanaka to uses his Vice Monitor ability to run the voting time suddenly, though it's failed as Ayame and Paru-kun found Yasuharu and stopped the voting time. After Mizuki Kurashina stated he will never forgive Karin for lying that Yuuma is the Chairman Marble, she stated she don't care and said she wanted to do this because Yuuma "killed" Zui back in the previous game. When Ayame injures herself in order to request Hako's helps, Karin recorded the video about it and sent it to Yuuma, in order to make him feel despair and taking revenge for Zui. This caused Yuuma gone "berserk" for once again, Karin is showed to be happy at this. Soon, along with every players was gives their smartphone to "Marble" (Which was Yuuma in his third stage of "symptom" wears Marble's mask). During Ayame went to challenge Yuuma 3, Karin is hyped to see this. After Yuuma returns back to normal and having a proof that he is not the Chairman Marble, Karin have no choice but revealed her true identity is the Chairman Marble to everyone (Though soon it's revealed that it's lying), Karin also stated that she is ready to being killed in the next voting result.
Soon, Mizuki called Karin out because he noticed that Karin was just lying. After hearing about it, Karin taking Mizuki's knife and tried to attack him, but Paru-kun comes to protected Mizuki from Karin's attack. The result ended up Paru-kun getting injured and Karin break the rule of no violence in the game, soon Sports Teacher Marble comes to giving her a punishment that she getting killed by Sports Teacher Marble. After Karin's death, the third voting was started and everyone is voting Karin, the result showed up and revealed that Karin is not the Chairman Marble.
- Mortal's Smartphone (人間スマホ, Ningen Sumaho) - Karin obtains the power of the God from Zui after she killed him. It allow her to uses any superhuman powers.
- Prediction - Karin can predict anything and the chance have at least 95% true.
- Lie - Karin can used the Mortal's Smartphone to lying the people. Karin used this to lying about Yuuma is the Chairman Marble.
- After Zui's death, Karin is the second character to using the power of the God.
- Originally Karin just want to use Zui, but after Zui "changed" her life, she decided to treat him as her master.
- It's revealed in Chapter 170 that Karin is the Chairman Marble.
- Although in the next chapter was revealed that Karin isn't the Chairman Marble but Paru-kun is.
- In the Anonymous Classroom's poll results, Karin received to most votes out all of the players (16 votes).