Dias Police: Ihou Keisatsu

There are roughly 150,000 illegal immigrants and illegal foreign workers in Tokyo. Those aliens have established a shady Metropolitan Government of the aliens, by the aliens, for the aliens. Public institutions such as government offices, courts, tax offices and hospitals exist within the shady government. Kubozuka Saki is the only police officer officially approved by the shady Metropolitan Government. This is a story of a mysterious man who protects and sometimes punishes aliens who can only live in the shady world. Today Kubozuka is again daring to and in the alien city of Tokyo.

(Source: Anime News Network)