Bakumatsu Aibou-den.

A single bullet cuts through Kyoto in the last days of the Tokugawa shogunate right before the restoration of imperial rule. Who plotted to assassinate Tokugawa Yoshinobu, who is about to become the last shogun of Japan? Was it the faction wanting to overthrow him or the rebels within the shogunate? Mutual enemies Sakamoto Ryoma, the wandering samurai, and Hijikata Toshizo, a deputy leader of the Shinsengumi and vassal of the Tokugawa clan, receive a secret order to track down the culprit. They are given a mere two days.