I forgot what the whole point of this story was. I know he's trapped in a BL book but what...

I forgot what the whole point of this story was. I know he's trapped in a BL book but what happened to the other characters that were supposed to be part of the plot...the characters are confusing cause you see them once and they have all this lore that happened in the book and then you dont see them again and then someone else pops up that has to do with the story line but I cant remember who they were. (╯°Д °)╯╧╧