At that time, Gozo Sone, the leader of the Kanto Sone family, was secretly planning to expand into Shinjuku. Sone sent Kuroda, a member of the Kansai Gyokudo, to Shinjuku and plotted to break up their territory. A series of disturbing violent incidents occur here and there in the entertainment district, and even Kano and the Ryu group, who do not operate in Shinjuku, are caught up in the chaos that Sone and Kuroda have created.
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