The Fate of the Returned Hero

One day, your average joe university student, Kashiwagi Yuuya was summoned to another world by a stupid goddess. His mission is to do what any cliche Isekai MC does; become the hero, get the harem, defeat the demon lords, save the kingdom/other earth and go back to earth. After doing all those menial shit, he was granted to go back to his original world with only a second passed despite wasting 3 years in his "hero" life.
Expecting himself to be an average joe again, much to his surprise, he still retains his powers as a hero. It seems his mission is just not over yet.
It's an isekai but not an isekai but technically an isekai? Just read it to find out!
From the popular web novel is now in manga form!