18+ Inyouchuu

Mikoto, her little sister Takeru, along with a mysterious talking black cat and their friend Yamato are the exorcist members of "The black cat demon slaying office" and of course it's their job is to hunt down demons. Things change when Takeru decides to take a phantom extermination job at Shunjuu Academy by herself. She soon finds out she's in more than what she bargain for.