Gen Sekine and Yasunobu Endo’s conflict

Gen Sekine and Yasunobu Endo’s conflict turns a struggle over money and property into the central murder case in the investigation of the disappearances around Sekine. Endo was reportedly blackmailing Sekine and intended to take his land, house, and kennel; Sekine killed him, and the effort to conceal what happened drew in other members of the underworld. The dispute’s consequences extended well beyond the two men: Endo’s disappearance became the strongest circumstantial case against Sekine, while the destruction and concealment of his remains made the investigation depend on testimony and persistence as much as physical evidence.

Background and the Stakes of the Dispute

Sekine was a dog breeder near Kumagaya with connections to organized crime. He had previously belonged to the Kyokuto-kai and, after arriving in Konan, was introduced to the Takada-gumi. His kennel business gave him a place in the underworld economy as a supplier of exotic animals, including dangerous dogs and a lion. That position brought him into contact with yakuza figures, but did not make him immune to pressure from them.

Endo was himself connected to that world and was regarded by Takada as an important subordinate. According to information obtained through one of Endo’s non-yakuza friends, Endo had been blackmailing Sekine and planned to strip him of his assets: his land, house, and kennel. The evidence identifies the intended seizure of Sekine’s property as the immediate source of the conflict. It does not explain how the blackmail began or establish that the two men’s dispute had a single cause beyond this pressure over Sekine’s wealth and business.

The planned loss was comprehensive: Endo was not merely seeking a payment but, as the account describes it, everything Sekine possessed. This made the kennel itself part of the conflict, connecting Sekine’s livelihood and underworld standing to the dispute. The relationship therefore sits at the intersection of personal intimidation and organized-crime economics, without the narrative supplying a fuller account of negotiations between the men.

Disappearance and the Evidence Against Sekine

When Endo vanished, suspicion focused on Sekine, but the case initially lacked a known location for the killing or a body. The investigation had to establish what had happened through a chain of circumstantial details. Sekiguchi later identified Endo’s murder as the strongest case against Sekine and said that witnesses could testify, though only indirectly, that Endo met Sekine shortly before he disappeared and was injured that day. Sekiguchi’s assessment was that Sekine had killed eight people, but he distinguished Endo’s case as the one supported by the strongest available evidence.

One detail fixed the last known hours of Endo’s disappearance. At 9 p.m., after illegal gambling, Endo called Yumi-chan and told her he would be late. The call did not explain where he was going or what happened next, but it gave investigators a specific point in the evening from which to trace his movements. Sekiguchi also learned that a local veterinarian had sold Sekine a large quantity of strychnine nitrate for putting sick animals to sleep. The purchase was a relevant investigative lead; on its own, it did not establish how Endo had been killed.

Information from Endo’s non-yakuza friend clarified the motive behind the suspected killing. Endo had been preparing to take Sekine’s assets, making the disappearance appear connected to the threatened loss of Sekine’s property. The account later reveals that Sekine killed Endo and his driver, Wakui, with poison. Shima, who drove for Ryoji Arai, learned what Sekine had done and helped bury the two men. The conflict thus drew in a second participant not as a rival to Endo but as someone who helped hide the consequences of Sekine’s violence.

Concealment and the Cost to Others

The concealment of Endo’s remains deepened the conflict’s consequences. Shima later faced pressure from Takada to reveal where Endo’s body was. But the remains could not simply be recovered: Shima had helped cut up and burn Endo’s body. His predicament was therefore not just a reluctance to identify a burial place. He had to answer a demand from a yakuza boss for the location of remains that, in any ordinary sense, no longer existed.

The pressure exposed competing demands within the underworld. Takada wanted Endo to receive honor in death and wanted Sekiguchi to have an airtight case against the killer. He also threatened Shima, while telling Sekiguchi he would not kill him if Sekine remained free and alive. The pursuit of a murder case consequently ran alongside the risk that a witness would be killed before he could provide evidence. Takada’s intervention helped drive events forward, but his private authority did not substitute for proof that could hold up in a police investigation.

Testimony, Arrest, and Resolution

Arai’s revelations changed the direction of the investigation. He said he had not participated in the disappearances of the last four victims; Shima had. Arai also reported that Shima had told him Sekine poisoned Endo and Wakui and that Shima helped bury them. The account made Shima central to the case, but the existence of the recordings and the pressure surrounding their disclosure complicated how the information reached the authorities.

After changing his name and marrying, Shima was eventually located by Takada in late November. Takada passed the information to Sekiguchi, who reported it to the Saitama police. Police arrested Shima in December, and, when confronted with the recordings, he gave them information that led to a search in Gunma Prefecture. There, investigators found enough of Akio Kawasaki’s teeth to support their case. The finding concerned another disappearance in the broader investigation, but it demonstrated how testimony about concealed remains could yield evidence even when the full bodies were unavailable.

On January 5, after the New Year’s holidays, the Saitama police announced the arrest of Sekine and his wife, Hiroko, for the dismemberment of Kawasaki. Sekine admitted almost everything within hours of his arrest. His admission and the evidence assembled through the investigation closed the Saitama Dog Lover Serial Disappearances case after an agonizing year of active inquiry and, depending on how the time is counted, more than a decade of disappearances. Endo’s conflict with Sekine had begun as a threat to Sekine’s assets; its eventual resolution depended on recovering the truth from the people who had helped conceal the crimes.

Significance of the Relationship

The conflict is not presented as a fully documented feud between equals. Its clearest basis is Endo’s blackmail and plan to take Sekine’s property; its decisive outcome is Sekine’s murder of Endo and Wakui. Much of what investigators learned came indirectly, through witnesses, Arai’s account, Shima’s testimony, and the later recovery of physical evidence. That uneven record preserves an important distinction between Sekiguchi’s strong suspicion and what investigators could establish as the case developed.

Endo’s disappearance also became the point at which personal coercion, yakuza relationships, and police procedure converged. Takada’s desire to pursue justice for his subordinate could accelerate the search, yet his threats created additional danger for Shima. Sekiguchi, meanwhile, needed evidence sufficient for a lawful case. The relationship’s lasting significance lies in that tension: a property dispute led to murder and concealment, but bringing the conflict into view required a fragile passage from underworld knowledge to testimony the police could use.