This is the first volume of four, that has a lot more action than words (unnecessary explanations, feeling explorations and emotions coming from tamed monsters). Worst-case scenario and Betrayal chapters are overkill and way too dramatic. All of the 1000 people forced summoned did not ask to go to another world, and probably most have no duty towards the world they came to so as to be able to help out and save the locals. Summoned people are called "saviors" by the locals. There is an unproven idea that if a savior becomes powerful, then with that incredible power they can return to Earth. Some of the saviors believe this because of their "game experience knowledge". Not facts, not truth. Nothing reliable. The truth is that all of the people that have been summoned in the past live and die in this new world. Some even get to die of old age. If author does not overkill, over-do, this chapter the main message of the story could have still been told. To have "saviors" that kill their fellow students and teachers just prove the lack of education, values and honor, the author and his characters have. A good person will try to do their best, a bad person can only expect the worst. To promote evil, to empower evil and over power evil makes normal people and good people give up hope even before their trials take place. Even though this is probably the best volume so far, this evil promotion and empowerment is a contradiction. If the author favors the evil antagonists so much, why didn´t the antagonists become the main characters of this story?
The keep is under attack from the out- and the inside. What exactly is happening? Can Majima Takahiro protect those he loves? Besides the usual character development and musing on the nature of humanity (sometimes dragging on a bit or a bit too obvious) it is also action packed. There is also much more going on than we might have expected, making me really curious about what comes next although with the current pacing it might be a couple of volumes before we get any definitive answers. Personally I like how a hero is made through experience and action and not just getting a cheat power, although I do find the outlook on people a bit on the negative side. I am looking forward to the next volume.
... Seriously. The only characters you can believe and have faith in in this series are members of the harem. No one else can be trusted. But even then, apparently members of the harem are fair game for dying, so don't get to attached to any of them while you read.