Kubota (久保田, Kubota) is an executive of the Kakyuu Association who becomes a target for Shunsuke Saruwatari when he is hired by the Shou Wang.
Shou Wang Arc
After the assassinations of Takashi Unoyama and Byeong-Hee Kim, Suzuki has all of the remaining Kakyuu Group executives moved into hiding hotels and holiday homes. Tony Lau, impressed by the murders of Unoyama and Kim, sends Saruwatari to kill Kubota next.
When Saruwatari arrives at Kubota's home in Munakata city, he finds a Murder, Inc. employee waiting for him inside. The hitman attacks him with a gun, but Saruwatari is able to dispatch him with his ninja sword within seconds.
The following morning, Suzuki and his subordinates play the security camera footage installed in Kubota's living room and recognize Saruwatari. Realizing that the rest of the Murder, Inc. employees will be useless against him, Suzuki is left only with the option of hiring a hitman from outside Japan.