Yatsuki Nishizuru works part-time in Akihabara and has the unique ability to see and talk to spirits, specifically the youkai that reside in the area. However, Yatsuki prefers to lead a normal life, focusing on work, caring for his younger sister Nanao, and enjoying a coffee at a nearby café. But all of that changes when he is unexpectedly hit in the face by a girl who falls out of a tree. This girl, named Rokka Ayatsuji, quickly becomes friends with Yatsuki and Nanao. However, they soon discover that Rokka is actually a Rokurokubi, an ancient youkai that feeds on souls and can stretch her neck to incredible lengths.
Complicating matters further, Yatsuki reveals that Nanao's body and spirit are separate, and Nanao is actually a ghost. At the same time, Momo Chitoseya, one of the waitresses at the café, gets possessed by an evil spirit. Yatsuki and Rokka carry out an exorcism to save her, attracting the attention of Nagi, Momo's sister, who is a professional medium. In exchange for their assistance in eliminating dangerous youkai in Akihabara, Nagi vows to find a way to reunite Nanao's spirit with her body.
Aware of the dangerous spirit world, Yatsuki embarks on a dangerous journey to restore his sister's spirit to her body, risking his life in the process.
