Because a large number of "exomorphs" suddenly appeared on the earth. They have independent consciousness and even have many abilities, but they are not willing to be disciplined at all. In order to find out the origin of these alien bodies, the government collected a large number of orphans and gathered them in an academy, let them form a contractual relationship with some of the "tamed" aliens, and then released them to explore the places where the aliens are most prevalent.
Motto: People are indeed valuable. But it has to shine brightly under the gray fog of fear