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22-year-old man gets 23 years in prison for murder of sex worker at hotel

20 Comments

A 22-year-old man has been sentenced to 23 years in prison after being convicted of killing a 31-year-old sex worker at a hotel in Tachikawa, Tokyo, in 2021.

The Tachikawa branch of the Tokyo District Court handed down its verdict Thursday against the defendant, who cannot be named because he was a minor when the crime was committed on June 21, 2021, Kyodo News reported.

The main issue during the trial was whether the defendant, who suffers from autism spectrum disorder, could be held criminally responsible for his actions. After his arrest, he underwent a three-month psychiatric evaluation and was found mentally fit to stand trial.

The defendant was first sent to a family court which sent him back to prosecutors who indicted him in March this year.

The court heard that the defendant checked into the hotel at 3:30 p.m. on June 1, shortly before the woman, Michi Mamoriya, arrived at 3:45 p.m. It is believed she and the defendant got into an argument because she used the room phone to call her male companion and asked him to come and help her. After that, the man stabbed Mamoriya around 70 times, prosecutors said.

When her 25-year-old companion arrived, he knocked on the door, then went into the room where he also was attacked. The suspect fled from the hotel, leaving a blood-stained knife in the hotel corridor. The male victim was able to call 119.

The suspect was arrested in Akiruno, Tokyo, on June 2. He was also charged with the attempted murder of Mamoriya’s male colleague.

Video footage, taken inside the hotel room before the killing, was retrieved from the suspect's smartphone. In the footage, Mamoriya warns the man not to film anything. The suspect then complies with her request, and the footage stops.

After his arrest, the suspect was quoted by police as saying he pretended to be a client when he arranged the meeting. He said he became “interested in killing someone” after watching a film of people being murdered on the internet. He also told police that “the sex industry was not helping with the declining birthrate and aging population” in Japan.

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20 Comments
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to call her male companion and asked him to come and help her. When her 25-year-old companion arrived, he knocked on the door, then went into the room where he also was attacked.

What other details about this companion? Is it more protection?

-4 ( +4 / -8 )

He also told police that “the sex industry was not helping with the declining birthrate and aging population” in Japan.

But killing and attempting murder does?

Alright, junior..........

13 ( +14 / -1 )

Once again lost for words. These types of crimes are far to frequent.

-3 ( +3 / -6 )

This animal will still be in his 40s when released. And the poor woman he cruelly slaughtered was just 31.

I just hope something happens to him in there and he doesn't get out.

Rest in Peace to the poor woman.

4 ( +7 / -3 )

If he is on the spectrum, there was no need for the last quip about his virtue signaling on the Japanese birthrate. The 25-year-old colleague sounds more like a pimp than a friend and should be considered liable in some way for enabling this - no one believes he was a friend.

-4 ( +1 / -5 )

Why not Gallows??..

Deserve it...

Rot in jail pathetic clown...

-1 ( +3 / -4 )

travelbangaijinDec. 15 11:54 pm JST

If he is on the spectrum, there was no need for the last quip about his virtue signaling on the Japanese birthrate. The 25-year-old colleague sounds more like a pimp than a friend and should be considered liable in some way for enabling this - no one believes he was a friend.

If he is going to express reprehensible views, we should get to hear about it. It is basically a hate crime. And pimping is not as bad as murder.

1 ( +3 / -2 )

"He said he became “interested in killing someone” after watching a film of people being murdered on the internet."

Horrible story. Looks like violent movies and video games are bending people's minds to do horrific things.

-1 ( +2 / -3 )

Why not Gallows??..

Probably because, once again, the convention that it must be 2 or more murder victims comes into play.

1 ( +2 / -1 )

Now he has plenty of time to focus his interest on being an inmate in Japan's harsh prison system.

2 ( +3 / -1 )

Autism spectrum disorder is not classified as a mental disease. It is a developmental disability and a type of neurodivergence, not a mental illness. My girlfriend is autistic, but also so very intelligent and aware of her surroundings, her learning capabilities are mind boggling. She gets really upset when she hears autism being used to excuse a crime.

1 ( +2 / -1 )

shogun36Dec. 15  05:14 pm JST

He also told police that “the sex industry was not helping with the declining birthrate and aging population” in Japan.

But killing and attempting murder does?

Alright, junior..........

Was he jealous or something? It's still murder. Dothe crime, do the time. Bye-bye.

-1 ( +0 / -1 )

thats a dark story. a storm of bad luck and terrible conditions for all involved.

0 ( +0 / -0 )

opheliajadefeldtToday  12:48 pm JST

Autism spectrum disorder is not classified as a mental disease. It is a developmental disability and a type of neurodivergence, not a mental illness. My girlfriend is autistic, but also so very intelligent and aware of her surroundings, her learning capabilities are mind boggling. She gets really upset when she hears autism being used to excuse a crime.

That's exactly the same thought I had. I have a friend who is very high up on the autism spectrum - one of the smartest guys I've ever known. We performed in a play once when we were kids, which was super long (ex: the main character alone had 300 lines). This kid memorized the entire script. It is despicable to use "being autistic" as an excuse for committing murder, as though it's some kind of mental illness - especially in a case like this, where he was actively seeking to murder someone.

-1 ( +0 / -1 )

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