A young boy, Kou Tenhou, realizes he has been reincarnated into the world of the Chinese-style RPG game "Kenshu Tairan Shiden." Remembering the future where his adopted sister, Ryuu Seirei, becomes a "nation-toppling evil woman" and he himself is executed as the "greatest villain under the heavens," he begins to move to avoid this ruin! His actions eventually have an unexpected impact on the original plot, and furthermore, he wins over beauties of "nation-toppling caliber" one after another as allies――!?