Kikan shita Yuusha no Gojitsudan

A college student named Kashiwagi Yuuya is summoned to another world as a hero. He endures many challenges and, with the support of his loyal allies, defeats the Demon King and the Evil God. He then returns to modern-day Japan, expecting the events to fade into a distant past. However, he retains all the abilities, spells, and items he had in the other world, remaining as powerful as the hero he once was.