Tom Sawyer Island is a city with strictly controlled information. The residents of this island use a visual information device called DECO (Decoration Customizer) to go back and forth between the Super Reproduction Space and virtual space. There is a numerical social credit system among the residents measured in units called "love". The amount of "love" one gets determines a resident's social standing, and this system is the reason for their peaceful society. Collecting a lot of "love" allows residents to expand their DECO capabilities, so residents scramble daily to collect as much as they can. On Tom Sawyer Island rumors spread of a Phantom ZERO, rumored to be causing a ZERO phenomenon in which "love" is lost. One day, a girl named Berry gets caught up investigating the mysterious Zero phenomenon of lost "love", and ends up becoming an invisible being called YUREI. Berry then meets another YUREI and a genius hacker named Hack, and joins the Ghost Detective Club. As Berry works to solve cases at the Ghost Detective Club, she becomes closer to uncovering the truths hidden on Tom Sawyer Island.