As a psychiatrist, Kouyou is prepared for just about anything from murderous psychopaths to narcissistic criminals and has no problem embracing the insane. But when he decides to uncover a closed case with an unsettling history, not only does he open a gateway to the truth but the problems that come with it. After one grave mistake, he soon learns who everyone around him really is putting a whole new meaning towards keeping friends close and enemies closer. Unfortunately, it's quite complicated when everyone has sharp teeth...