Yatsuki Nishizuru is an individual who works part-time in Akihabara and has a unique ability to communicate with spirits known as youkai that inhabit the area. Despite this, he tries to lead a normal life by working, caring for his younger sister Nanao, and visiting a local maid cafe. However, Yatsuki's life becomes more complicated after an accident where Rokka Ayatsuji falls onto his face. She quickly befriends him and Nanao until they discover that she is actually a Rokurokubi, a soul-eating youkai with the ability to stretch her neck. At the same time, Yatsuki learns that Nanaos body and spirit are separate, making her a ghost. Meanwhile, one of the cafe maids, Momo Chitoseya, becomes possessed by a dark spirit. Yatsuki and Rokka work together to exorcise the spirit, drawing the attention of Nagi, Momos sister who is a professional medium. She enlists them for youkai extermination in exchange for Yatsuki defeating more dangerous youkai in Akihabara. With this newfound responsibility, Yatsuki must put his life at risk to return Nanaos spirit to her body.
Monster Girl has been published in English as Yokai Girls by Seven Seas Entertainment under the Ghost Ship imprint since January 2, 2018.