For the manga, please go to Mitsuko Souma (Manga). For the film, please go to Mitsuko Souma (Film).

"Mitsuko Souma had died. Physically? Several seconds ago. Mentally? Ages ago."

--- Mitsuko's death scene.

Character Information
Mitsuko Souma
Position: 6th
Kills: 7 (Megumi Eto, Yoji Kuramoto, Yoshimi Yahagi, Takako Chigusa, Tadakatsu Hatagami, Yuichiro Takiguchi, Kayoko Kotohiki)
Killed by: Kazuo Kiriyama
Cause of Death: repeatedly shot in the chest, head, back, and face
Chapter Death: 69
Assigned Weapon: Sickle


Not much is known about Mitsuko Souma's (相馬光子 Sōma Mitsuko) childhood. Mitsuko states that she never had a father, though it is not clear whether her mother raised her alone from the start or if he had left before she was old enough to remember. At nine years old, her mother took her to an old building in a run-down neighborhood where three men paid her mother to gang rape her and videotaped the events. When Mitsuko confessed to her teacher, an adult that she thought she could trust, what had happened the teacher raped her in the reading room after school. Mitsuko's best friend at the time witnessed the rape and spread a rumor around school instead of trying to help Mitsuko, which resulted in the teacher getting fired. Mitsuko's mother tried to take her again to be raped for money, but Mitsuko accidentally killed her. She cleaned up the scene on the staircase to make it look like a robbery gone wrong, and afterwards she sat on a swing in the park. She was then taken to live with distant relatives where their child harassed Mitsuko. When the child had died after falling off of their roof, the mother wrongly accused Mitsuko of killing her, but Mitsuko was defended by the father who began sexually abusing her shortly after. Being repeatedly violated in her youth and being hurt by people she thought she could trust shaped Mitsuko into a manipulative young woman who used her sexuality to get what she wanted, unable to trust others.

One of her most infamous moments at her school happened when Mitsuko convinced some boys to arrange a "hit" on a rival girl gang leader who had personal connections with the Yakuza; a car hit the girl and nearly killed her.

Mitsuko is feared by all of her classmates, even Takako Chigusa. She had a reputation that is widespread all over the school. She did drugs, larceny, blackmail, prostitution and shoplifting with her gang that consisted of Hirono Shimizu and Yoshimi Yahagi. Though Mitsuko is never described to have bullied other students herself, she was still greatly feared since she was their leader. She is even said to intimidate any teacher with just a look, which shows how widespread her reputation is.

Despite the fact that others are well aware of the fact that she's bad news and is probably one of the most dangerous students in the Program (supported by her reputation and history of gang activity), nearly everyone she has come across has fallen victim to her. Tadakatsu was incredibly suspicious of her, and yet he was easily seduced. Hiroki admitted internally that he wouldn't have been an exception to being among the many who would've done anything for her, even with the knowledge that she was dangerous, but "special circumstances" kept his head cleared.


Mitsuko is one of the most beautiful girls in class alongside Takako Chigusa and Sakura Ogawa, and is popularly described as "angelic". According to Shuya Nanahara, Mitsuko has "the gorgeous looks of a pop idol", and Hiroki Sugimura compared her beauty to that of a yuki-onna. It is also noted that Mitsuko always wears a "strange, listless" expression. Yuichiro Takiguchi describes the look in her eyes as scary, but "at times really sad and kind". Despite being the most beautiful girl in their school, none of her classmates would approach her. 

"Here we had a teenage Yuki-Onna. She’s charming, innocent, angelic, yet completely cold. Under the moonlight, her eyes were like gleaming ice."

Friends and EnemiesEdit

Though Mitsuko doesn't have any real friends, she does lead a gang which includes Hirono Shimizu and Yoshimi Yahagi. The three of them regularly engage in activities such as prostitution, mugging, and larceny. The gang's victims were almost always older men, whom the girls seduced before taking advantage of them. Despite spending a lot of time with her, Hirono knew not to trust Mitsuko, and Yoshimi joined simply for escapism.

The majority of the girls in her class feared her; including Takako Chigusa, although she never would admit this, and the guys in the class such as Shinji Mimura realize how beautiful she is but chose not to pursue her due to her reputation. The only person who was willing to give her a chance was Yuichiro Takiguchi, though he was too shy to talk to her.

In the ProgramEdit

The First VictimsEdit

Mitsuko decided very early on that she was going to participate in the Program.

She headed toward the residential area and entered a house where she heard a cellphone go off. It was Kinpatsu Sakamochi, who was informing Megumi Eto to turn off her cellphone. She called her out, found her and told Megumi that just like her, she was scared, and wanted to team up with her. Megumi was relieved and consumed with guilt, hugging Mitsuko, and told her how sorry she was for thinking about killing her. As they embrace, Mitsuko slit Megumi's throat with her sickle; it turned out that Mitsuko had been acting the whole time, and apologized to her corpse while revealing her intentions: she had also intended to kill Megumi. Mitsuko expresses that she needed to be more careful from then on.

She next came across Yoji Kuramoto and Yoshimi Yahagi in a argument and when the two began to make up, Mitsuko sneaked up and stabbed Yoji in the head with her sickle. Mitsuko stated she was only doing it to protect her friend, but Yoshimi is too angry at Mitsuko for killing the only person who understood her. Mitsuko, upon realizing that Yoshimi is no longer an option as an ally, shot her dead with the gun that Yoshimi had. It was revealed that she intended to use Yoshimi as a human shield.

Now that she had a gun, Mitsuko walked around the island with ease. She then witnessed the fight between Takako Chigusa and Kazushi Niida. Takako won upon defending herself and saw Mitsuko. The two talked briefly, and Mitsuko spoke about how Takako was always a better girl than her and used to be so pretty. Once Takako realized that Mitsuko was talking about her in past tense, she began to run but Mitsuko managed to shoot her down in her attempted escape.


Mitsuko attempted to sneak up on Hiroki Sugimura, but thanks to his GPS he saw that she was behind him and knocked the gun away from her hand. Hiroki saw Takako before she died and had learned who killed her and was not going to fall for her manipulation due to the sole circumstance of Mitsuko being his best friends killer. At first, Mitsuko tried to convince Hiroki that the gun was Takako's and that Takako had tried to kill her, and how scared she was and that she was glad to run into Hiroki. Once she realized that Hiroki wasn't buying into her act, she revealed that she did kill Takako and thought that she had died immediately. Despite the fact that Hiroki was holding a gun to her head, Mitsuko was supremely confident in speaking to him and (correctly) doubted that Hiroki could even pull the trigger. She then attempted to entice him with sex, but Hiroki denied her advances. Mitsuko then revealed her traumatic past to Hiroki, who had asked her how she could be so cruel. She stabbed him in the shoulder with Megumi's knife and swiftly escaped.

As she traveled, she thought about what to do since she now only had her sickle as a weapon. She quickly realized that she had no chance against the machine gun shooter (Kazuo Kiriyama) who she will probably eventually fight with just a sickle. She then saw Tadakatsu Hatagami, who was peeing in the bushes. She tried to sneak up on him to kill him, but she is spotted by Yuichiro Takiguchi before she could strike. Tadakatsu wanted to kill Mitsuko as he didn't trust her and sees the sickle in her hand, correct in his suspicions that she had just attempted to kill him, but Yuichiro believed that they had to give her a chance and it would be good to have another member in their group so they could meet with others and leave, as well as give her protection. Mitsuko decided to play along with them to avoid death, acting afraid and innocent all the while, allowing them to check her for other weapons. Her hands get tied up with a belt until they can figure out what to do with her. Tadakatsu decided to take a nap, with Yuichiro watching over Mitsuko in the meantime. Mitsuko and Yuichiro talk for awhile; Yuichiro told her that he believes that she isn't as bad as their classmates say she is since she seems to have a sad, kind look in her eyes. To him, there had to be a reason for why she was the way she was, and that it wasn't her fault for it. Mitsuko is surprised to be touched by his words, although it is not enough to change her plans. He eventually untied her hands so she could have a drink from his bottle of water and Mitsuko is still surprised that Yuichiro is showing so much kindness to her as no one had ever shown her kindness before. Tadakatsu eventually woke up and took over.

It is during this time that Mitsuko decided to kill Tadakatsu while Yuichiro is sleeping. Although Tadakatsu was short with her, Mitsuko used the fact that he was attracted to her advantange, subtly seducing him to lower his guard. She then asked to be alone with Tadakatsu in a clearing farther down, away from Yuichiro, where she began undressing. In the middle of foreplay, she attempted to slit his throat with a razor blade (her signature weapon hidden in her panties) but a bird had made a loud sound, causing him to turn his head and making the cut shallow.

Tadakatsu was angered by her murder attempt and they both wanted to get the gun first. Mitsuko realised that she wouldn't reach the gun before him, and she bolted into the bushes. Tadakatsu shot after her, though he missed and Mitsuko ran her way back from the shrubs to Yuichiro, who had woken up due to the gunfire and was at a loss: both tried to convince Yuichiro to listen to them, but both stories seemed possible to him as Mitsuko claimed Tadakatsu tried to rape her and that she had to defend herself with her nails while Tadakatsu is claimed that Mitsuko was trying to kill him.

Hoping to keep the situation from escalating, Yuichiro asked for the gun from Tadakatsu so they could figure things out. As this was going on, Mitsuko decided to steal the gun when it would reach Yuichiro's hands. However, Tadakatsu flipped the gun before it reached Yuichiro's hand and pointed the gun at Mitsuko, firing. In an unexpected turn of events, with Mitsuko certain that she was going to die, Yuichiro took the bullet for her. As he fell to the ground, Mitsuko quickly took the baseball bat and bludgeoned Tadakatsu to death with it. She then went back to Yuichiro (who was dying of his bullet wound), having concealed Tadakatsu's corpse from his vision and lied to Yuichiro about Tadakatsu's fate; telling him that Tadakatsu ended up running away. Yuichiro expressed that he was sorry that he couldn't protect her any longer, asking if she is okay. She hugged him, kissing him gently and then shooting him in the chest three times to put him out of his misery. She thanked him for making her feel a little happy, closing her eyes in remorse, and kissed him again.

Mitsuko's EndEdit

Having walked for hours, Mitsuko eventually came across Hiroki Sugimura telling Kayoko Kotohiki to build two fires and listen to a birdcall while he was dying. Instead, Kayoko decides to stay with him as it was her fault that he died. Mitsuko sneaked up behind her, inquiring Kayoko if she wanted to die, although Kayoko never realized in her grief that the voice speaking to her was not in her head. After Kayoko replies "yes",   Mitsuko asked, "Why don't you go ahead?" and shot her twice in the temple. She greeted Hiroki, evidently disgusted at his "sacrifice"; his death being in vain. As Mitsuko turned around, she mused about how Kayoko Kotohiki should have seen the obvious.

As Mitsuko was collecting the weapons dropped by Hiroki and Kayoko, she gets shot several times in the back by Kazuo Kiriyama. As Mitsuko registers the pain, she berated herself for not hearing Kazuo sneaking up on her the entire time, as well as not being clever enough to decipher Hiroki's plan of building a fire like Kayoko had. As Mitsuko began to fall, she briefly began to flashback to her past and tried to figure out what made her the way she was. Upon her self reflection, she was resolute and stated internally that she will not lose. Despite her fatal wounds, Mitsuko managed to raise her gun and shoot him four times in the chest.  However, Kiriyama's bulletproof vest caused the bullets to merely bounce off. He then fired off another round of bullets at Mitsuko, this time directly in the face, quickly killing her. It was described that the sight was as if a strawberry pie had been smashed into her face. Although Mitsuko had just physically died, it was noted that she was already dead inside to begin with.

Notes and TriviaEdit

  • Mitsuko was the fourth student to murder a fellow classmate, and was the first girl to start killing her classmates.
  • She is one of four girls in the program to kill a boy, the others being Takako Chigusa, Noriko Nakagawa and Kayoko Kotohiki.
  • The novel is the only version where she kills seven classmates, in the manga and the film she only kills six.
  • The novel is the only version where Mitsuko and Takako have a talk before she kills her.
  • She is one of the seven students who's lost their virginity.
  • Mitsuko had the second highest kill count at 7.
  • The novel is the only version where Mitsuko is the second last female student to be killed, in the manga and film she is the last.
  • Mitsuko killed both of the people Hiroki Sugimura wanted to save, Takako Chigusa and Kayoko Kotohiki.
  • The novel is the only version where Mitsuko considers making an "ally". It is revealed that she wanted to use Yoshimi Yahagi as a human shield to increase her chances of surviving.
  • Hiroki is the only person in the novel that Mitsuko talks to about her past and her motivation for participating in the Program.
  • The chapter when her death occurred, 69, is the number that is associated with sex, possibly referring to her childhood sexual abuse and trauma.