Requiem

In a post-apocalyptic world divided in the New and Old World, people are trying to survive. There's a bloodthirsty murderer in their midst.
Both Yukiko Mitsukai and Stephen March have lost relatives by the hands of this perpetrator.
Together with her friends Ji Lang, Eagle Eye and Gerekko Dai, Yukiko and Stephen March will try to find a lead to the killer of her parents and his half-sister.
The police, Chief-Inspector Norino Vastai and his two adjunct-inspectors are trying their best to catch this criminal, but they are always one step behind.
As they discover the truth bit by bit, they see that there's a big conspiracy between ruthless people from both the Old and the New World and that the serial killer isn't their only enemy.