BEGINNING

One day group of students summoned to another world, people of that world called them heroes, who will defeat demons and save the humanity. but things go wrong with certain otaku and he was left alone in labyrinth.

He decided to find a way out of labyrinth and return to his own world.

At the same time students were summoned, certain slime demon lord along with his loyal wolf sucked into a rift between space, instead of transport to another world they were place which is gap between universe where he meet him.

( I don't own tensura or arifureta, credit goes for original writers)