Sousei no Tenken Tsukai

Sousei no Tenken Tsukai summary:

Known not only as the young lady of the distinguished family of Chou that safeguards the northern regions of the Empire, but also as accomplished in the literary and military arts, as a woman of unparalleled beauty and intelligence, Hakurei is a young, beautiful girl adored by the people. “It has been---10 years since I saved you, and we started living together. I want to be the one to have your back.” “...Man, what a troublesome Young Lady you are!” The one to save me, Sekiei, the undefeated hero from 1xxx years ago who was reincarnated, from the brink of death was her. Ever after that, we have continued to live and train together in the Chou Family as siblings. However, time has brought the maelstrom of war. The war against the foreign race begins--- “Did you see the swordmanship of the young master?!” “And his arrows never miss the target either?!” I shall make use of my past life as a master martial artist and together with Hakurei, we shall be peerless as we accomplish great things!! The reincarnated hero and the beautiful young women’s warring, sword fantasy begins!!