Space Sweeper (kknn)

An era when mankind began to spread to multiple star systems. Companies that purify the environment of the planet and allow human beings to live have been born one after another and have grown rapidly. The work of these companies is to clean up harmful creatures, broken and dangerous robots, radioactivity, etc., and "clean up" to a state where humans can migrate. Depending on the environment of the planet, a huge amount of material is required for cleanup. However, we can not transport all the n...