It is now year 16 of the Meiji era (1883 AD). 43 years have passed since Jinya left all he knew in Kadono and set off on a journey to grow stronger. In that time, he's forged a somewhat peaceful life for himself at Demon Soba with his daughter and friends.
But if Jinya's many years have taught him anything, it's that nothing lasts forever--a lesson made all too clear as he once again crosses paths with Suzune, his sister who is determined to become the Demon God. As their reunion threatens to change not only the trajectory of his own fate, but of those around him as well, Jinya will finally give his answer to the question posed long ago: "Human, for what purpose do you wield your blade?"