Tenko no Ouji: Tsuzurao no Ken, Hirameku

Ao Amakawa is an orphaned boy studying medicine at Sacred Mountain. However, two men suddenly appear and tell him to fulfill a promise made 150 years ago by the Emperor. "You are the reincarnation of the Prince of Heavenly Fox." The Prince of Heavenly Fox led the Nine-Tailed Army in battle 150 years ago. Ao's fate is changed by his encounter with nine Heavenly Foxes, all of whom are destined to follow him. A Japanese-style fantasy begins, with nine swords flashing!

(Source: Ichijinsha, translated)