<figure id="attachment_446869" class="wp-caption alignnone" style="width: 479px;" aria-describedby="caption-attachment-446869"><a href="#" data-ident_hash="e5c113fe"><img src="https://res.cloudinary.com/fridaydigital/image/private/t_article_image/wpmedia/2025/11/de7abeff7d67eab3debad9fecea88716-e1763347898144.jpg" alt=""></a><figcaption id="caption-attachment-446869" class="wp-caption-text">A scene showing offender C assaulting A-kun (from a video recorded by the offenders)</figcaption></figure>
<h2>Violence disguised as sparring</h2>
“After the incident happened, I noticed something was wrong with my son, but I brushed it off. I still regret it to this day.”
The mother of A-kun (15), a high school boy who was repeatedly assaulted by two teenage boys on the Yodogawa riverbank in Osaka this June, forced out her words as if chastising herself. The offenders were A-kun’s former middle school classmates—and friends.
The assaults took place twice, on June 12 and 15.
On the 12th, one of the offenders, B, sent A-kun a LINE message around 6 p.m.: “I wanna smack A, come over.” He called him to the riverbank. After 8 p.m., the other offender C and a friend joined. C punched A-kun dozens of times, while B kicked him from behind.
B and C referred to this assault as sparring. After the second round of sparring, they cornered him: “Are we doing a third round, are you paying money, or are you going into the river?” A-kun took off his school uniform and chose go into the river. The entire scene was recorded on a smartphone by C’s acquaintance.
Three days later, on the 15th, A-kun was summoned again. That day too, C assaulted him, but this time he brought a different friend. In total, aside from B and C, three other boys were present as spectators during the incident.
As previously reported in FRIDAY Nov. 14–21 issue, A-kun suffered facial contusions, left thigh contusions, and other injuries requiring approximately three weeks to heal. On September 30, Osaka police referred B and C to prosecutors on suspicion of assault and coercion. A-kun’s mother recounts the incident (below, quotes are from A-kun’s mother):
“They and my son were classmates in the middle school rugby club, and my home had always been their hangout. Even after the incident happened, B and C casually kept coming over. They even came when I was making dinner. When I asked, ‘Do you two want to eat too?’ they said yes, and we all sat at the table together.
But at that time, only my son looked nervous, like he was tiptoeing around B and C. Still, friends fight sometimes, and friendships have ups and downs. I brushed it off as something like that.”
A-kun has had developmental disabilities since childhood and has been bullied before for not being able to express himself well. Each time, his mother intervened to resolve the issue.
“My son never had friends, so I treasured the friends he finally made. I also knew that B and C were a bit wild. To be honest, a part of me hoped, ‘Maybe they’ll protect my son from bullies.’”
<div data-friday-nextpage-lead="&quot;I got hurt playing rugby.&quot;"></div>
<figure id="attachment_446868" class="wp-caption alignnone" style="width: 1536px;" aria-describedby="caption-attachment-446868"><a href="#" data-ident_hash="eb026adf"><img src="https://res.cloudinary.com/fridaydigital/image/private/t_article_image/wpmedia/2025/11/3ca6011a308fb28f939d6cf0b1c1cfe4.jpg" alt=""></a><figcaption id="caption-attachment-446868" class="wp-caption-text">A-kun being forced to kneel and having his head stepped on by the offender (from a video recorded by the offenders)</figcaption></figure>
<h2>His bloodstained school uniform</h2>
There were other signs of trouble. After the incident, A-kun was covered in bruises and limping. Even so, his mother believed his lie that he had been injured playing rugby. She became worried when she saw him walking while supporting himself against the wall. When she asked what was wrong, he replied, “I’m fine. You’re annoying—don’t talk to me.” She assumed it was just typical teenage rebellion and did not question him further.
But the truth came out from an unexpected place. The video of the assault—recorded by B and C’s friend—began spreading. A friend of A-kun’s younger sister, after seeing the video, contacted her saying, “Your brother is going to be killed if this keeps up.” This was about ten days after the assault.
“At first, my son tried to protect B and C. I kept telling him, ‘This is a matter of life and death—please tell me everything,’ again and again. Finally, he said, ‘They kept hitting me over and over, and in the end they pushed me into the river. I was really scared.’”
A-kun’s mother immediately contacted the families of the boys who were present at the scene. The next day, boy D—who had recorded the video—and his mother came to visit. Several videos of the assault were found on his phone. As A-kun had said, “D tried to stop them,” the videos contained D’s voice saying, “Stop it, leave him alone.”
“D told me he was told, ‘If you’re going to stop us, then go home.’ But he said he couldn’t leave because he thought A might be killed if he wasn’t there. So he kept pleading, ‘Please stop, for real.’ My son said that’s why B and C finally backed off.”
Afterward, D went to the Yodogawa Police Station and gave a detailed statement about what happened on the 12th. A-kun and his mother filed a criminal complaint.
“I’m a single mother and always busy with work. I often got home late and wasn’t properly watching my child’s condition. And during that time, this happened to him… After the incident, I blamed myself. Why couldn’t I protect him? Parents think they are watching their children, but in reality, we often aren’t.”
To keep from worrying his mother, A-kun secretly washed his bloodstained school uniform and the underwear soaked with river water.
“Normally my son leaves his clothes all over the floor—he never does laundry. How could I have missed such an obvious sign? I’m ashamed of myself.”
The offender boys’ parents also failed to notice their own children’s wrongdoing. Some even said, “My child would never do something like that.”
“As parents, we want to believe our children. I understand that. But we have to notice when something is off in what they say. I overlooked my son’s SOS.
My son told me, ‘I didn’t want to trouble you. You’re already having a hard time with work—I didn’t want to make you suffer more.’ And I told him, ‘That’s not true. What would hurt me most is losing you. What hurts me most is you being hurt. So tell me anything, anytime.’”
She says she hopes that even one fewer parent will have to suffer as she did—and that is her prayer.

 Kei Kato

 The mother of a high school boy, A, 15, who was assaulted multiple times by two teenage boys on the banks of the Yodo River in Osaka City in June of this year, squeezed out a few words as if to warn herself.

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