In August 2005, Kudo shocked the yakuza world when he became sworn brothers with new Yamaguchi-gumi godfather Kenichi Shinoda in a sakazuki (sake-sharing) ceremony. As a result of the ritual, the Kokusui-kai became an affiliate of their former enemies, the Yamaguchi-gumi.
On February 15, 2007, he was found dead bleeding from an apparent self-inflicted gunshot wound.[1] The suicide followed a rash of shootings and retaliations between Kokusui-kai and a rival gang, Sumiyoshi-kai, over gang territory, including the shooting death of Sumiyoshi-kai's boss. The shootings ended with an agreement between the Kokusui-kai and Yamaguchi-gumi to stop fighting on 8 February.[2]