Inu to Yuusha wa Kazaranai  

Sousuke Satou was an 18-year-old high school student who was suddenly transported to another world where he defeated the demon king and returned to Earth after several years of absence. Despite struggling to find employment on Earth, he encountered a battle between a "magician" and a "monster" that he believed did not exist on Earth. Despite his ease in defeating monsters, his powers attracted attention, leading him to become involved in demon subjugation. Now, the former strongest hero is taking part in modern supernatural battles!