Minase Youmu to Hontou wa Kowai Cthulhu Shinwa

A high school girl named Minase Youmu is taken to the mountains by unknown individuals who claim she has consumed a mysterious "medicine," making her return impossible. A former detective named Sanpouji Kotetsu discovers her and intervenes, taking her to the police. There, investigator Naru Asuka and her psychic partner Hayama Reiichi become involved in Youmu's case. The three must determine who captured Youmu and what the effects of the medicine are before any irreversible consequences occur.