He Killed, Dismembered, and Hid his Sister’s Body in his Room

The terrible murder of model and actress Azumi Muto.

Being part of a family is a blessing and a curse. To be loved, nurtured and part of a loving family is everyone’s dream. Enjoying meals, holidays, birthdays, weddings, and other family events help bond people and create lasting relationships. However, sometimes being part of a family can be tough.

Some families are dysfunctional with parents who abuse their kids or each other. There are families who cheat, lie, and steal from each other. And sometimes, when there is no love and only friction, some families break apart through fighting, divorce, and in extreme cases murder.

This story is about the Muto family, a wealthy, well-educated, and close family with dentistry in their blood. The Muto family is made up of dentists from generations and with many properties and clinics run and passed down through the family. However, two members, brother Yuki and sister Azumi would be the two black sheep who would not become dentists.

Azumi decided she wanted to be a programmer, model, and actress instead of following her parents, grandparents, and other relatives into dentistry. And Yuki, would not practice dentistry because he decided to murder and dismember Azumi. Why did he murder her? What did he do with her corpse? How was he caught?

Azumi And Yuki Muto

Azumi was born on June 13, 1986, and was the youngest of three kids. She had two older brothers and the family lived in Tokyo. They were part of a long line of dentists and both of Azumi’s parents, her grandparents, her oldest brother, and other relatives were dentists. Azumi’s grandfather had started a dental clinic in Shibuya Tokyo in the 50s and her parents were hoping all their three children would also become dentists and join the family business.

Along with the dental business, Azumi’s parents also owned many real estate properties and both Azumi and her brothers were directors in the family’s real estate company. The family was obviously wealthy and the futures of all three children were guaranteed to be affluent. That is until Azumi and Yuki ran into problems.

Azumi was actually in school and studying to become a computer programmer. Because of her good looks and bright personality, she was also working as a model and actress on the side. But there was pressure from her family and a push to try to get her to stick with the dental business so Azumi actually left home for a few months at the end of 2004 when she was 18 years old. She decided to create a stage name and focus on her modeling and acting career.

She even was cast in a role for a small budget movie called “Cream Lemon” which was based on an anime. But she returned home and decided to continue her schooling and modeling while living at home. She also often had problems with her middle brother, Yuki. Despite Azumi being bright, intelligent, and optimistic, her brother Yuki was different.

Yuki, who was the middle child, just one year older than Azumi was very interested in becoming a dentist like his older brother, parents, and grandparents. He said he, “wanted to be part of an environmental conservation effort by using his earnings as a dentist to buy a desert and plant grass to create an oasis.”

He was in dental school but kept failing the entrance exams required to become a dentist. He took the exam three times and failed each time. He felt pressure on him to pass and was attempting to take the test his fourth time. Unfortunately, Yuki never got around to taking the fourth exam.

Unlike his brother and sister, Yuki couldn’t quite achieve the success that his siblings could. He always came across as quiet, weird, and a loner. A friend of Azumi who was interviewed recalled, “Azumi once said to me that she doesn’t talk to Yuki because ‘he’s creepy, I don’t know what he’s thinking and he makes me feel scared.’”

Another friend of Azumi also told police, “She was really wary of Yuki. A few years ago, she said her older brother was really lecherous and he kept on leering at her with lustful thoughts on his mind. She was really scared. Everybody who heard what she said was really worried for her, but nobody really knew what to do.”

Despite the incestuous connotation from the friend though, police stated that Yuki did not have any romantic or incestuous thoughts about his sister and that tabloid gossip was not accurate.

But despite the police’s denial, Tezukayama Gakuin University psychology Professor Makoto Oda felt differently when talking about the relationship between Azumi and her brother Yuki.

“The suspect, the brother, seemed to have always had some sort of tunnel vision. All he saw happening in his life was growing up, becoming a dentist and taking over the clinic. He and his sister were extremely close in age and there’s no way they could not have had some sort of sexual feeling going on between them. There are definitely the elements needed for incest in place there. Normally, these feelings are strongly suppressed, but it is the female who generally perceives them more than the male. I think the girl must have realized something was going on.”

Whether there was anything sexual going on or not is unknown but what is known is that Azumi felt uncomfortable about her brother and days before she died, she told friends she was worried about his mental state.

The Crime

On December 30, 2006, both Yuki and Azumi were home alone. Her parents and brother were visiting family in Fukushima during the Christmas and New Years' holidays. The details of what happened that day were described to the police by Yuki who confessed to killing his sister.

Around 3 pm on that day, Azumi was talking to Yuki about his constant failures on the dental entrance exam. Yuki said he was tired and angry from constantly being reminded of his shortcomings so he took a wooden sword which is commonly used in Japan for the sport kendo, and bashed her over the head repeatedly. Her face was swollen and hurt but she was still alive and fought back. Lashing out at him, she continued to berate him saying that he had no real dream or purpose in life since he was only following what his parents wanted.

Yuki’s anger boiled over and he grabbed a towel and began strangling Azumi explaining he, “killed her in order to shut her up.” According to Yuki’s confession, he learned from a TV show that humans die after being strangled for 180 seconds. So Yuki continued to strangle Azumi while counting to 180.

After 180 seconds, Azumi was still breathing so he took her to the bathroom, put her in the bathtub, and held her head underwater until she drowned. He then wiped up the bloodstains that had occurred from their fight.

He then decided to dismember the body in the bathroom with a knife and a saw. He separated the body parts and put them in four garbage bags hiding them around his room. He also sliced off Azumi’s breasts and her genitals and put them through the garbage disposal. He told police he did that so no one would be able to identify if the body was a male or a female.

He then stole one of Azumi’s panties and left the house to go to his study camp. No one was home and the dismembered body of Azumi remained in the house until January 3rd when Yuki’s brother and parents returned from Fukushima and found the bags. The family suspected that Yuki was involved and called the police.

The next day, police arrested Yuki when he returned home from the camp. Once news of the murder was released, many tabloids started reporting that Yuki was a necrophile and cannibal who raped and ate parts of his sister. But the Tokyo District Public Prosecutor’s Office denied those claims saying they were false.

Arrest & Sentencing

Since Yuki confessed right away and explained the details of the crime, there was no doubt he was guilty. However, the defense team for Yuki was trying to prove that Yuki was not mentally capable of taking responsibility for the crime.

The psychiatrist who examined Yuki said his mental state at the time his sister died was unstable.

“At the time of the murder, he had diminished capacity of such an extent it would have been extremely difficult to judge from right or wrong, while the mutilation of the body occurred while he was criminally insane and not capable of being held legally responsible for his actions.”

Prosecutors however felt that the bad blood between Azumi and Yuki was slowly building until Yuki finally decided to kill his sister. Yuki expressed that he hated his sister because she was not only mean to him but had a bad attitude toward her parents as well. Despite the siblings not getting along, their father told the court that he didn’t think their relationship was so bad admitting, “I should have known before it happened.”

Yuki was charged with murdering his sister and the desecration of her corpse. Originally, in May of 2008, the Tokyo District Court had found him guilty of the murder and gave him 7 years in prison. He was acquitted for the mutilation and dismembering of her body on the grounds that he had diminished mental responsibility.

However, The Tokyo High Court rejected the reason with Judge Fumihiro Abe saying, “a written statement [by Yuki] submitted to police gave a chronologically organized and detailed account of events leading to the incident and the crime, suggesting that he had a clear memory of events.”

The Tokyo High Court instead increased his 7 years to 12 years in prison.

Regardless of it being 7 years or 12 years, Azumi lost her life and a family was ruined because of Yuki’s actions. Whether the family’s pressure was too much for Yuki to handle, or as he said the belittling by his sister Azumi was the cause, we will never know.

Unfortunately, two of the three children of the Muto family will never follow in the family business, and one who was a rising star will never have a chance to do anything. The pressure of succeeding and the hate for his sister culminated in him taking her life and ruining his own. Hopefully, Yuki will be able to reflect on his actions and will come out of prison as a more mentally stable and reformed man.

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