“I’ll Explain the Meaning of Yama-Trino’s Hand Sign,” Former Tokyo Police Detective Reveals His Identity

Signaling her ties to the group

Rino Tazawa (27), a top cabaret club hostess who also posted videos on YouTube under the name “Yamatorino,” was caught in the act and arrested on suspicion of violating the Narcotics Control Act after allegedly possessing 0.4 grams of cocaine at her home. She was subsequently rearrested on suspicion of using cocaine and ketamine.

Rather than cannabis, a so-called gateway drug, she had apparently gone straight to cocaine. Reports that she possessed 21 bags also attracted attention, but what made the biggest impression was her defiant smile when she was referred to prosecutors and the hand sign she made while being transferred.

Seated in the back of the vehicle, Tazawa used the thumb, index finger, and middle finger of her right hand to form a shape resembling the letter “C,” holding it up for the cameras of the press.

People offered various interpretations: “Was she trying to send someone a message?” or “Was she showing that she refuses to be intimidated by anything?” In fact, however, the hand sign represented the number three in “San Tama.”

Some people apparently noticed that rapper KENNY-G, who is based in Fussa, Tokyo, had made a similar gesture. I once interrogated him myself, and directly asked him at the time, “What does that sign mean?”

His answer was: “San Tama.”

The term refers to an area comprising North Tama, South Tama, and West Tama, encompassing 30 cities and towns, including Tachikawa, Hachioji, Machida, and Fussa. In other words, the sign indicated that Tazawa was associated with the group around KENNY-G and others based in the San Tama area. It was a gang sign for “San Tama.” I believe she wanted to convey that she was one of them.

Former Metropolitan Police Department inspector Akiya Hirano (53) joined the force in 1993. He spent approximately 24 years investigating crimes committed by antisocial forces, including yakuza and hangure groups, in departments such as the Fourth Organized Crime Division and the Anti-Boryokudan Division. A highly skilled former detective, he received 14 awards from the Superintendent General, as well as numerous awards from the Criminal Investigation Department and Organized Crime Control Department. He reveals what is happening in Japan’s underworld today.

The Hangure groups of San Tama

In January this year, the Tokyo Metropolitan Police Department established a task force to target Kohei Ikka, a second-tier group under the Sumiyoshi-kai. The group was suspected of having deep ties to anonymous and loosely organized criminal groups, known as tokuryū, involved in illegal recruitment scams, fraud, and robberies arranged through illicit job offers. Police had been monitoring lounges and cabaret clubs in Roppongi and Nishi-Azabu, after receiving information that some of the women working there were closely associated with yakuza members.

“Let’s go for a bike ride after the after-party.”

That was the signal. “Bike” (charinko) is slang for cocaine. Apparently, when a customer made this declaration, the cabaret hostess would happily go along with him.

However, their aim was not to get high on cocaine, but to sober up. Taking cocaine supposedly sharpens their awareness, allowing them to drink more alcohol.

The hangure groups serving as bodyguards for wealthy regular customers who sponsored these bike parties were often brought along wherever the customers went. In recent years, hangure groups from San Tama had become particularly conspicuous around Roppongi. It is said that the drugs supplied to them came from Group X, a subordinate organization of Kohei Ikka.

When it comes to tokuryū, the Tokyo Metropolitan Police Department has singled out Natural, one of Japan’s largest illegal scouting groups, as the most dangerous tokuryū and launched a major investigation aimed at dismantling the organization. Amid this crackdown, former police sergeant Daisuke Jimbo of the Anti-Boryokudan Division was arrested in an unprecedented scandal for leaking investigative information to Natural. Jimbo was my colleague and had been assigned to the investigation into Natural since the fall of 2023.

The Metropolitan Police Department immediately imposed a gag order following his arrest, so I had no choice but to learn the details from media reports. Apparently, Jimbo had been in contact with Natural chairman Hiroaki Obata and had obtained information from members through a messaging app developed independently by the group. After he was removed from the investigation due to personal problems, he allegedly began leaking the locations of surveillance cameras and information about planned raids.

In March this year, Jimbo was found guilty and sentenced to one year and six months in prison, suspended for three years.

Some time later, I received a direct message on Instagram from someone whose profile picture was the character Toru Amuro from “Detective Conan.”

It was Jimbo.

[Read the second part here] Former MPD Fourth Organized Crime Division Inspector Akiya Hirano Speaks Out: What He Learned from His Encounters with Yakuza Members

From the November 6, 2026 issue of “FRIDAY”