@DHENZELOVE tags will be updated as the story progresses, unfortunately we don't really know what exactly the genres are, as the publishers don't use the same ones that we do.
Great one. Saginomiya said he writes the story inspired by the Sekai-kei genre.
Two of the well known representative of that genre for the Showa-born folks are Iriya no Sora, UFO no Natsu, and Saishuu Heiki Kanojo. Heisei generation might be more familiar with things like Shinkai Makoto's works.
Notice the pattern on how those kind of story usually ends...