I don't mind this long fight, after all it's a important fight for everyone.
For Mc, because his life will obviously not be the same as this first one. That means no encounter with Irene or any friendly relationship with her, his family and childhood crush friend alive and powerful, etc.
For Tina, because well, it's kinda obvious she is a important character here, if not the main girl of this story.
For the demon's people, because they will not be controlled by a maniac king like this dude here.