Normal world with normal people , or is it. That's what a person's mind ask it's self everyday.
Tajima ask himself that question. He's a sixteen year old guy that lives in Japan , Osaka and he's still in high school , he goes in Shokuna High. Tajima is a nerd without glasses , but he's smart , gets bullied all the time. The boy has a good life after school he's a ZeeTuber(YouTuber) and he's popular as a gamer , he got 250K followers.
Of course Tajima has that girl she likes so much in his class , they call her Nami. Nami is a girl that is not that famous at school , she's a bookworm ( she loves books a lot ). The problem with Tajima he's afraid to confess his feelings to Nami , because he fear's rejection.
So it's around that time in high school where you do a presentation in front of the class about your family ( to do a family tree in front of teenagers , how embarrassing at that age). So Tajima doesn't know any thing about his previous family members , so he ask the family about the family tree , they told him to look in the attic for a box that is written they're second name ( they're second name is Nobara).
He found the box and he saw one book it was a journal , the family never saw it before. Tojima took it to his room and it was a journal on how to summon a devil. Tojima didn't believe it , but he thought how about he Livestream this thing maybe it would boost his followers. He did the Livestream. What happens next find out soon.