Nippon Sangoku: The Three Nations of the Crimson Sun depicts the near future of Japan, where revolution arose from nuclear war, natural disasters, and corrupt governance, where civilization has collapsed. The nation has split into three, entering an era of warring states vying for supremacy. Aoteru Misumi, once a humble local government official, aims for the "reunification of Japan," rising through the ranks with his vast knowledge and exceptional eloquence.