Konya mo Serial Killer to Machiawase

From Seven Seas: Crime is ever-rising, a fact that police officer Shiro Isogai lives with every day. After the brutal murder of his fiancée, Isogai has been working tirelessly to find the killer. Suddenly, a “mysterious informant” begins popping up, helping the police locate serial killers one after another. Isogai knows this could be his chance for closure and decides his only hope is to team up with this person. But when it comes time to meet the secretive ally, he's surprised to be face-to-face with a young woman, Kuroi Hinata. Teaming up with Hinata and her “sixth sense,” Isogai prepares to hunt the city's deadliest criminals and find the clues he needs to catch his fiancée's killer.