High school student Saginomiya Iori is a commonly loner who was a loner in his class, as for Iori, he is summoned as a hero with his classmates in a different world.
That place was a fantasy world with sword and magic.
In such a world Iori got a skill at a space he visited by the summoning process from a gaudy goddess and he lives in the different world with this skill now. That kind of story.
YANDERE is Japanese culture (‘ ω ‘)