Ichinomiya Kantarou was raised with the sight of demons, yet he faced isolation and harassment from those who lacked that gift. Consequently, he forged friendships with the demons, developing a deep bond to their realm. One day, Kantarou learned of the mightiest demon, dubbed the ogre-devouring Tengu. Enthralled by tales of its power, he pledged to locate this creature far surpassing all others and vowed to name it Haruka upon discovery. From that moment, Kantarou scoured distant lands for the ogre-devouring Tengu without success, earning a living as a folklore author and demon hunter. In the remote heart of the mountain range, a legend whispered among villagers for generations of the ancient tales. During one assignment, he finally uncovered reports of a nearby shrine said to house the sealed ogre-devouring Tengu.