To best answer this question, we should examine direct quotes from the murderers subsequent to getting caught, as well as testimonies from those around them.
Here is a quick summary before we dive in:
- Hiroshi Miyano: tried to hide his identity as much as possible after being released from prison. He is known to disappear when people discover who he actually is.
- Jo Ogura: openly brags about the things he did to Furuta.
- Shinji Minato: appears irritated when people ask him about his criminal background. Has complained about his incarceration.
- Yasushi Watanabe: little is known about him. He is said to have become one of Japan’s “hikikomori” following his release from prison.
Now let’s examine some quotes and testimonies directly:
On April 17th, 1989, the police were questioning the boys as to why they confined Furuta in Minato’s house for over 40 days :
When asked why they confined the victim for over 40 days, the boys stated that they were “afraid of getting caught by the police”. When an investigator asked them if there was any other reason besides fear of getting caught by the police, one of the boys retorted, “what other reason would there be?”
『朝日新聞』1989年4月17日朝刊第一社会面31面「○○さん、一度は外へ 少年の両親が逃がす 女高生殺し」
There was an approximately one hour long documentary about Furuta’s murder made around the time of the boys’ trial and Furuta’s funeral. The documentary can beed here :
From 27: 55 to 28: 40 in the video, a reporter comes up to Miyano’s mother to question her about Furuta’s murder:
Reporter: “Could I speak with you for a moment?”
Miyano’s Mother: “Could you please stop?”
Reporter: “So, we heard that none of the boys’ parents have apologized to Miss Furuta’s parents for the crime.”
Miyano’s Mother: “Excuse me.”
Reporter: “Have you contacted Miss Furuta’s parents yet? Can we hear from you any thoughts or feelings you would like to convey to Miss Furuta’s parents?”
Miyano’s Mother: “I don’t think I can.”
Reporter: “Have you made any kind of contact with her parents?”
Miyano’s Mother: “Could you please stop?”
Miyano’s Mother: *runs away from the reporter with her bicycle, gets on the bike, and rides off*
From this, we can see that Miyano’s mother is quite annoyed with people asking her about it.
Now let’s take a look at some of the things Miyano was up to after being released from prison in 2009. Keep in mind that Miyano (known in Japanese as “主犯A” or “Criminal A”) was arrested for wire fraud in 2013, but was released due to lack of evidence:
(Click on the picture to unblur it)
Yellow text in the bottom right corner: “His favorite saying was “I stuck it in her mouth so far that she threw up”.
White text on the bottom: “When I heard the rumor, I couldn’t believe it. So I asked him over a drink. The stuff about you being one of the perpetrators of the concrete-encased high school girl murder case (Murder of Junko Furuta) is a lie, right? His facial expression suddenly stopped and turned pale. This happened in August of this year. The next day, I stopped receiving any contact from [Miyano], even though I had been spending almost every day with him.”
The photographer, mister M, said this with suspicion. M presented a photo where there was a shirtless man sitting on a bench throwing a peace sign.
“That man (Miyano) called himself “K”. We met around 3 years ago. I joined a gym in Western Tokyo where I was commuting. He felt like a big brother to me, and invited me to hang out with him. This picture (panel 3 with the three guys in suits with Miyano (K)’s face blacked out and the two guys around him with pixelated faces) was taken at a barbecue we had earlier this summer. It was a time when I really didn’t know about the murder incident…”
The end of 1988 marked the murder of Junko Furuta. The murder case, which is described as the “deeds of savages hiding under their masks,” is well known more than 20 years later. However, after having been released from prison in 2009, what became of [Miyano] was largely unknown.
“I could have never envisioned myself being so close to such a brutal criminal. But in retrospect, realizing he was one of the main perpetrators [of Furuta’s murder] isn’t that surprising. He was always talking about Judo (martial arts) or sex, and would brag about how when having sex with women how he “stuck it in her mouth so far that she threw up”. He also talked about how much he liked choking women during sex. He is also 43 years old, and that is certainly his face right there. Friends of mine who have also met K would send me photos of [Miyano] and say that this is unquestionably the same person.”
The photo [of Miyano] released at the time of the murder incident [in 1989] certainly bears a striking resemblance to the photo [of K] taken in August earlier in the summer. His well-featured nose, the so-called “gyoza ears” so prevalent in Judo practitioners, and his symmetrical hairline. “A hairline is like a fingerprint in that it is unique to each individual.” Like a plastic surgeon, even if 30 years have passed, such a coincidence is further deepened.
M continues talking.
“And that’s not all. [Miyano] was said to have been arrested for fraud in January, and around the same time [Miyano] was arrested, K suddenly disappeared for 2 weeks. Because it was around New Years, I thought we should all go out drinking together, so I tried calling [K] but I couldn’t get a hold of him. Later, when I asked [K] about where he had been, he claimed that he got in trouble with a rental car and so he was brought to the Akasaka Police Station, but looking back in retrospect there’s no way that could’ve been true. The reason why is because K told me directly that he knew a lot of people engaging in a group wire fraud scandal.”
There is even more evidence that [Miyano] is K.
In the spring of this year, a reporter from a certain weekly publication called the gym that M was a member of asking for information about [Miyano]. This became a topic of gossip among the other gym members. In fact, the reporter actually came to the gym to cover something.
“But at that time I wasn’t really paying attention. The person who told me that K was actually [Miyano] was a guy who served 12 years in Chiba Prison. This guy told me that he had met K in Chiba Prison and was like his underling. [Miyano] got 20 years in Chiba Prison too, right? That guy let loose a secret while drinking and said “brother, the media is still chasing you for the [Murder of Junko Furuta]. Must be rough, huh?””
When M last met K, K was driving around in a BMW, he had a Hermès wallet, a gold Daytona luxury wristwatch, and overall seemed to be doing well. He is engaging in [fraudulent] multi-level marketing, and there are plenty of LINE messages from him nagging at his friends to engage in fraudulent activities.
It cannot be said that he was made to pay for his crimes after serving only 20 years in prison. To kill that girl in such a sorrowful and gloomy manner, and not even apologize or explain his actions to [Junko’s] bereaved family. This magazine intends to pursue more information [relating to Miyano].
From this, we can see that Miyano is trying is best to hide his involvement in Furuta’s murder. Let’s examine one more article about him:
(Click on the picture to unblur it)
“It wasn’t just in the gym. He (Miyano) would have both his juniors and his friends call him “K” in private, and would even have his name recorded as K in matches (Judo/Kickboxing). He even wrote his name as simply “K” on his resumé, which I got to see.”
This is what our informant, who was treated and cherished like a younger brother by Miyano, had to say. During the summer, [our informant] happened to overhear that K was actually [Miyano]; when [our informant] questioned [Miyano], [Miyano’s] face turned pale and abruptly cut all contact with [our informant].
So what has K been up to since then?
First, his whereabouts. No matter how nice and friendly [our informant] has tried acting towards K [after discovering his identity], K has refused to so much as let him enter his house.
“[Miyano] will dodge the question by saying that his house is too cluttered, and he won’t even come to hang out with me when I suggest we can meet somewhere other than his house. However, I do know where he lives. He was living in a small town by the riverbank of the Tama River. At least, that’s were he was living until August. That address is the one that was written on his resumé, and he would pick up the phone whenever I called the number associated with that address.”
This “small town by the riverbank of the Tama River” is not a very well-known place, and is just a residential area you’d find in any suburb with a few shopping districts around the train station. When we went to the exact address, we found it to be a still new apartment building. [Miyano’s] apartment nameplate wasn’t anywhere to be found, but there’s no mistaking that he’s here. However, when ringing [Miyano’s] doorbell or banging on his door, no one came out.
There is still one clue we have to ascertain [Miyano’s] whereabouts: Ikebukuro. It is said that [Miyano] frequently comes to Ikebukuro to go drinking.
“K often said that many of his juniors are there. When [Miyano] was arrested by the police in January, those involved in Ikebukuro were paying money.”
[Miyano] was arrested in January for wire fraud. We got to see the exact location in Ikebukuro where K and the Ikebukuro group were meeting. However, when we questioned the Ikebukuro group [about Miyano], they all refused to tell us anything.
“Well, I don’t know. Because I don’t know what kind of relationship it is, I won’t say anything,” said one of the former scam group members.
[Miyano] has disappeared yet again. This time we got to see what deep, dark connections he has.
In both of these articles, we see that Miyano tries his best to keep his involvement in the murder hidden, and that he disappears when people figure out who he is. It’s as if he knows that what he did was wrong and he wants to absolve himself from his responsibility.
Ogura was released from prison in 1999. He is said to have learned some IT skills while in prison and worked at some kind of firm after his release from prison, but got fired because the people around him knew of his involvement in Furuta’s murder . He later joined a gang, where he was reported to have said the following :
“When I was a boy, I went to jail for 10 years. I had put a girl in confinement, and one day when I came back to the house from when I went out to play, the girl was dead. So I lit a cigarette and put it next to her nose, and the smoke didn’t move at all. That’s how I knew she was dead,” Ogura bragged while laughing
『産経新聞』2004年7月28日大阪夕刊社会面「女子高生コンクリ事件の元少年 監禁致傷 罪状認める 東京地裁」
『読売新聞』2004年7月28日東京夕刊社会面23面「『オレは女を監禁し懲役』 コンクリ詰め殺人の元少年 監禁再犯、初公判」
A year after this quote (2004), Ogura would go onto kidnap and beat one of the gang members he bragged about this to in what is known in Japanese as the 三郷市逮捕監禁致傷事件. At 2: 00 in the morning on May 19th, 2004, Ogura beat one of the members of his gang on the street and threatened him with a bat. He then kidnapped the man and drove him 40 minutes away to Misato City where he said the following while beating the man :
“You’re the one who took my woman. I’ll kill you. I have killed before.”
『産経新聞』2004年7月4日大阪朝刊社会面「女子高生コンクリ殺人の元少年 男性監禁、暴行で起訴 東京地検」
It’s almost as if he perceives his past murder as a badge of honor. So he clearly hasn’t learned anything since Furuta’s murder.
Minato, for the most part, went under the radar following Furuta’s murder. However, on August 19th, 2018, Minato repeatedly beat a man on the shoulders with a baton and stabbed the man’s neck with a knife. After getting arrested for this, he had the following to say about his former life in prison for Furuta’s murder :
“Prison is nothing but hardships, and is not an environment where I can confront my past crimes. Even after being released from prison, society is just too difficult, so of course I couldn’t face my past crimes.”
Here’s another quote from Minato from the same source:
“In various articles [written about me], they say that I am beyond rehabilitation. These people have never met or spoken with me, so they have no idea how I’ve been living my life, so why do they arbitrarily write these things [about me]? Idiots.”
It appears that he is complaining how the prison system didn’t rehabilitate him and that it is somehow their fault that he committed another crime. One can read more about what he had to say about his 2018 crime here  .
Again, very little is known about him. This is just about all I can find :
[Watanabe] was released from prison in 1996 and became a hikikomori. In January of 2001, Eisuke Inoue, a reporter from the Mainichi Shinbun, contacted Watanabe’s mother and began interviewing them in the spring. On April 8th, 2001, the contents of the interviews were published in an article. The article was met the both sympathy for Watanabe as well as harsh criticism, with people arguing that the material was “too sympathetic to the perpetrator” or “rubbing the feelings of the victim’s bereaved family the wrong way”. In turn, Inoue said that “the pain the victim’s family was going through was beyond his imagination. I looked through the court records and reports on the case as much as I could, but somehow disregarded how brutal the case was, and am still bewildered by it even after finishing the interviews. Having read my readers’ criticisms, I better understand the difficulty of compensating for one’s crimes.”
I cannot find Mr. Inoue’s original article or the specific criticisms it received. But from what I can imagine, it probably had something to do with Watanabe feeling so pressured by society that he joined a gang and started committing crimes. Because some comments were sympathetic towards Watanabe, I assume he expressed some kind of regret regarding his crime.
So in short,
- Hiroshi Miyano is embarrassed about his past and doesn’t want anyone to find out about it. He gives himself ridiculous names like “K” to mask his identity.
- Jo Ogura is proud of his crime and has been known to openly brag about it. He even committed a similar crime in 2004 against someone who he had previously bragged about Furuta’s murder to.
- Shinji Minato acts as if the crime is none of his business, and blames the prison system for not rehabilitating him.
- Yasushi Watanabe probably expressed regret concerning his crime, but this is not certain.
Some of the quotes I used for this answer I took from one of my previous answers on this case, so check it out if you’re interested: