It starts with a group of people (and an entire net cafe) suddenly isekaied to and stranded in an inhospitable environment. Social cohesion breaks down quickly, and a violent thug begins dominating and abusing the group. There are repeated rape, torture and murder scenes, with the emotional stakes amped up to maximize the suffering and degradation of the victims. The thug is obviously the villain, but his power, control and virility are emphasized so much that it feels like "ugly bastard" NTR fetish porn. And it just goes on and on like that. Very unpleasant.