Don't Call it Mystery Manga Omnibus Volume 7 collects volumes 13-14 and features story and art by Yumi Tamura.

When a family friend of Detective Furomitsu dies in a mysterious accident, the young woman returns to her hometown of Toyama to investigate. And just for good measure, she brings Totonou with her! While there, Furomitsu gets a call from her boss, Aoto, who tells her that police stations around the country are receiving anonymous messages warning of a serial killer in Toyama. Worried for Totonou's safety, Furomitsu urges him to leave while she continues her investigation alone. But before he can take off, another dead body shows up on the shoreline!