Comments of chapter undefined of Extra's Magic

Why didn't he tell her that it wasn't a connection, but a way to share the mana as well? Why did he steal the core from the beginning? A short, annoying plot followed him up, searching for his movements, and also why is he so stupid? Many points could have been avoided. Also the dungeon that took many useless chapters or his provocation and killing of the devil and not trying to hide his face before entering the devil’s lair despite his knowledge of the last scenes of the dead man. Many stupid conspiracies have been added and also where is the anger? Oh stupid man, he wants to imprison you and put people to follow you. Is it not important and don't get angry? The devil also has fun and kills, and no attention is paid to him. The entire story revolves around the hero, and very little of it shows the world or the other characters and the background of the other characters, with the exception of three or four.