Eiji Urashima looks like an easy-going college student, but he had lived a harsh life as a boy, being bullied and harassed because "his real father was a serial killer". Eiji, who hides the fact that he is carrying a heavy cross called "son of a serial killer", has a loved one. Her name is Kyoka Yukimura. Eiji was able to forget the unpleasant things and laugh heartily during the time she spent with Kyoka when a murder takes place. Eiji has completely lost his memory of the time period during which the murder is said to have occurred. After that, considering various circumstances, he realized that he had a dual personality, and said, "The one who committed this bizarre murder was the 'other me' who inherited the blood of his fearsome serial killer father. Ha..." Eiji was tormented by fear and anxiety. In order to find out the truth of the matter, Eiji made up his mind to embark on a “journey of self-discovery”, where earth-shattering facts are revealed one after another!