First, the historical background of speculation
I don't know how many years ago, a sudden disaster happened, which was an unprecedented geological disaster. This disaster destroyed human civilization, and most people died in an instant disaster.
Second, the current situation of mankind.
In this catastrophe, a floating fortress escaped this catastrophe. Survivors in the sky named it "lighthouse", which means "illuminating the last future of mankind".
This lighthouse is not a utopia. In this utopia, the class division of the lighthouse is very serious, divided into dust people and upper-class people. The factor that distinguishes them lies in genetic differences, and the upper class people are genetically flawless.
At present, there are several major departments in the lighthouse, including medical department, hunter, bishop of light and shadow, supply management department, and dust people responsible for the daily maintenance of the lighthouse. Among them, "wild hunters" are well trained and have excellent combat power. They can bring back key materials such as energy, medicine and food from the ruins on the ground, and they are responsible for the supply of this lighthouse.
Among them, the residents on the lighthouse have the value of contributing points. If the contribution points are insufficient, they may be abandoned when they need first aid, and the population reproduction of lighthouses is strictly restricted.
These settings show that the whole lighthouse is a system designed entirely for survival, which is very realistic and cruel.
Third, the enemies that mankind meets.
In the animation, there are powerful creatures named beast-eating and thorn method. Spine method has no pain, and can release a pheromone called scarlet, which will cause hallucinations when inhaled by people. Spinning can parasitize humans and manipulate them to fight.
The strength of autophagy is far stronger than that of human beings, and it is also helpless for the hero and heroine to encounter autophagy. Human weapons have limited lethality to it. The king-level autophagy is mentioned in the animation, which shows that autophagy is also hierarchical.
At present, the lighthouse is loaded with electromagnetic weapons, which can fight against the king-class autophagy beast, and the power system of the lighthouse is paralyzed for three minutes at a time, which shows the powerful strength of the king-class autophagy beast.
Only two episodes of animation have very complicated backgrounds, which are probably masterpieces in the plot.