Kanawa no Kage Rui

Japan has yet to become one unified country. A sudden cease-fire prevails in the fighting between the Yamato Imperial Court and the native Emishi people over Japan's northeastern Tohoku region. An Imperial Court envoy visits Aterui, the chief of a great Emishi tribe. The envoy who calls himself Sanekage proclaims, "Let's go on a journey to hunt a demon together."

A demon created by a shōmoji entertainer in the Imperial Court had suddenly started attacking people indiscriminately. Aterui had no reason to lend a hand to his careless enemies, but he decides to embark on this journey due to Sanekage's offer related to revenge for Aterui's wife.

(Source: Anime News Network)

Note: Includes 3 extra chapters.