To Chie Souma, a female college student, every day feels depressing when she has no luck with job hunting. She’d much rather end up in an alternate universe, just like in her beloved tripping into another world novels...... Just as she was dreaming of escaping this reality, one day she actually trips into another world! It might be too dangerous in a female body to survive in this world. Chie decides to use the knowledge that she’s gained from reading, lie about her gender, and become “Souma the scholar”, but---!? A manga adaptation of a strategy manual style fantasy.

At first glance, the Fukuoka city seems like a peaceful one, but under the surface, crime is running rampant. The city's Hakata ward is home to the professionals of the underworld: professional killers, detectives, informants, professional revenge seekers, those skilled in torture, and more. And according to urban legend, even a “killer of professional killers” exists in the city. When stories of the men in the underworld are told, a “professional killer murder” appears.

A manga anthology based on the DMM Games/Nitroplus browser game Touken Ranbu -ONLINE-.