Juhwan and Minjae are the biggest wimp duo in their high school. One day, when Minjae was involved in a car accident, the spirit of Taesu, a psychopath criminal who had been executed in the past, reborn in Minjae's body. Juhwan finds out what happened to his friend, and he tries all he can to stop the killer instinct. This story began with a simple question, "What if your best friend suddenly turned into a merciless psychopath killer?". The story portrays a wimpish boy and a psychopath, who start to find out and understand each other little by little. Aren't we all just human beings after all?