A half-demon with white hair and golden eyes had once fell in love with human priestess. Both betrayed by each other, they sought to kill one another. The half-demon was running off with the shikon jewel, the priestess had shot him in the heart with an arrow. 50 years passed since then.

You come from the modern era. On your way to school, you fell down a bridge and landed in the feudal era. While stumbling around, you meet the half-demon who’s pinned to a tree.