In the tumultuous Warring States period of Hinomoto, a mysterious group known as 'Saikashu' wields guns under the banner of 'Yatagarasu' in the uncharted region of Kinokuni. Led by the foreign arrival Magoichi, they stand as a formidable force. Meanwhile, Saburo, wary of encroaching European threats, fights to defend Hinomoto. Their paths, destined to remain separate, intertwine amidst the clash with foreign invaders, altering their fates in unforeseen ways!