The 8th Tokugawa shogun, Yoshimune, sets up a suggestion box to hear the complaints of the common people. However, not all the complaints were addressed. Kuroda Gunbei, a vassal of the senior councilor Okubo Kaga-no-kami, took it upon himself to pick up unresolved cases. Along with his subordinates, he worked to rectify wrongdoings and bring about resolutions.
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