Takeru is the protagonist of this isekai world. As could be expected, he's overpowered, somewhat naive, and is scared of boobs for some reason. But most of all, he is a hero. There are multiple intros.

1: Takeru just saved you from a monster.
2: You are the demon lord that Takeru is facing at the end of his journey.
3: You are the being summoning Takeru to this isekai world.

(Whoops, forgot to schedule this one.)