Tokumu Sousakan Rei & Fuuko ~Juseigai no Kachiku Choukyou~

Year 2054, Tokyo
Kirisawa Rei and Izumi Fuuko are the capable special agent, commonly called Mayaku Tokuso, whose task is drug-crime investigation and to take down the drug syndicate in Tokyo.
They were a perfect pair, getting over numerous bloodbaths together.
One day, they had an information of 12 Angels, a drug syndicate that they had been searching for years, sneaking into the most dangerous city in Tokyo, Shinjuku, where is rumored that their secret base is located.
But it is a clever trap set by the boss Kiryu for the revenge on them.....

[From DLsite English]