I am fiercely protective of my son and would do anything and everything in my power to protect him if he was wronged. So I can totally understand a mom in Japan who went to extreme measures to expose the boy who beat up her teenage son. Her son was trying to help a friend when he confronted another teen boy in Kumamoto. The poor boy had no idea his attempt at being a good friend was going to land him in the hospital.
That’s what happened, however, when the other boy severely beat him. In an effort to get justice, the mom turned to a popular social media account to expose her son’s attackers.
The mom immediately made a plan to press charges.
In the video, the woman’s son can be seen being relentlessly beaten by another boy. The boy delivering the attack stomps and kicks the other boy’s head in addition to straddling him and pummeling his face and choking him, the Tokyo Reporter reported in January 2026.
The boys are surrounded by others who began shouting “Die!” as the boy gets attacked. No one attempts to step in and help him.
“I’m beyond angry, I’m just numb,” the boy’s mother told TV Kumamoto, according to the Reporter. She also expressed worry there might be “other victims.”
The mom said her son was only trying to help a friend who had been extorted for money by the assailants.
“He had bruises all over his body and face,” she explained to the Reporter. “His nose was swollen and his forehead was swollen about 10 centimeters across, so he was taken to the hospital by ambulance. I think the 20 people around him who were filming the incident are just as guilty.”
At the time, the mom was in the process of talking with Kumamoto Prefectural Police about pressing charges against those who attacked her son.
In a desperate attempt at accountability, the mom did what she could.
被害者の中学生は、後輩が金を脅し取られたことを知って助けようとしただけなのに、逆に20～30人に囲まれてボコボコに殴られ蹴られ…
— いちか (@nBwQSzmg3qU2ysd) January 9, 2026
頭を執拗に狙われ、全身打撲＋顔面の腫れがひどくて救急搬送→そのまま入院（2日間)という重傷です。… pic.twitter.com/nMzdGIYfZU
Eventually, the video of her son’s beating made it back to him. “This is it!” she thought, she told The Asahi Shimbun.
Three days later, she shared the video on her own Instagram account, asking people to “please share.”
Additionally, she offered a message to her son’s attackers. “Those who do not come to apologize will face social sanctions. We know your school, so be prepared,” she warned.
After she shared the video herself, someone informed her they had shared the video with the person who runs the “exposé account” called Deathdol Note on X.
One person changed things for her.
【拡散希望】
— DEATHDOL NOTE (サブ垢) (@deathdolnote) January 12, 2026
ご本人のご希望により、被害者の母親のアカウントを公開いたします。
今後、熊本で発生した殺人未遂事件に関する新たな情報は、こちらのアカウントから発信されます。被害者を救うため、拡散のご協力をお願いいたします。@a_asashima_s
The account, which started in 2024, shares videos with the intention of exposing crimes and bullying.
Masato Kosaka, the 37-year-old man who runs the account, told The Asahi Shimbun that he found the video “sickening.”
“Schools and police have repeatedly covered up bullying,” he told the outlet. He also shared that his “goal is to cause a stir on X and get the adults to act.”
A victim of bullying himself, Kosaka said that no “major secondary damage” happened as a result of the videos he posts online, despite claims by others saying he is “becoming a bully” by exposing people on social media.
“If we don’t do this kind of activity, the cover-ups will continue,” he explained. “I think a certain amount of secondary damage is unavoidable.”
On January 16, 2026, police arrested the 15-year-old boy who attacked the woman’s son, Fuji News Network reported via the Tokyo Reporter. When he was arrested, the boy admitted his guilt. “I was angry, so I used violence to injure him,” he said.
