A normal boy who accidentally entered a world that is endangered to be conquered by a demon lord. He got kidnapped together with his classmates and got separated from his best friend. Later on they got summoned by the king of the country and explained everything. They were considered as spawned heroes from another world. All of them have attributes contributing to their powers but one boy. He didn't have any among all of them. He find ways to be useful to his friends and for the country. He used his talent and knowledge about their world to survive the first wave, but he got betrayed and got stuck inside one of the apocalyptic gates. Later on he learned everything from this world, he found new friends, got stronger and stronger as he explored more of this world and became the king. After five years he went back to his classmates and showed how "badass" he has become.