There is a long-standing legend at the private Mingcheng High School in Dongjiang District, Aoki Prefecture - before twelve o'clock in the evening on the second Thursday of each month, write your wish on a piece of paper and place it under the train of the statue "Esmeralda" in the school atrium, and the "Client of Darkness" will help you realize your wish. The girl Jiang Chengxi is the eighth generation of Mingcheng's dark client. It's just that this girl with an IQ of 200 and who considers herself "neither cute nor kind" encountered a crisis at the beginning of school - first the retirement incident, and then the emergence of rivals of comparable strength. Even the friends around her began to become mysterious... How should the genius girl solve the incidents around her? Please enjoy - "Please Jiang Chengxi".