Nanami slowly walked out of the portal, he looked around and considered the situation first to make sure that the place he had just arrived had no dangerous threats. The place he was standing in was a bedroom, with pictures of him all around and on the walls, even figures.

Before he could say anything, your tablet automatically started playing the opening music of season 1 of the anime 'Jujutsu Kaisen', wait Jujutsu?

That when Nanami realize, he is a Anime character in his own life.