Fukuoka is Japan's sixth largest city and the largest city on Kyushu Island. Located on Kyushu's northwestern shore, it is the capital of Fukuoka Prefecture and is historically a city of samurai. In-series, 3% of its population of 2.5 million are killers. The two central wards of Fukuoka include Hakata, the city's commercial district, and Chuo Ward, its administrative district, and outlying wards include Higashi Ward and Sawara Ward.
Locations within Higashi Ward
Higashi is a ward of Fukuoka that lies east of Hakata.
Hakozaki is the neighborhood where the detective Takeda is murdered in his apartment in the first light novel. In the third light novel, Xianming Lin and Zenji Banba visit Takashi Unoyama's office to kill him, and the third victim named Noriaki Hiyashi lives in the same neighborhood. His house is where Lin is reunited with Feilang. Appearing on the cover of the fifth light novel, Hakozaki Shrine (筥崎宮, Hakozaki-gū) is a Shinto shrine that hosts one of Fukuoka's three major festivals.
Locations within Sawara Ward
Sawara is a ward of Fukuoka that lies west of Chuo Ward.
Momochihama is a neighborhood of Sawara Ward along Fukuoka's coastline, where Fukuoka Tower and the 35-floor apartment building where Yusuke Harada lives are located. Yusuke shares the top floor with one of the players for the Fukuoka SoftBankHawks.
Fukuoka Tower appears on the cover of the second manga volume. At 234 meters, it is the tallest seaside tower in Japan and has a viewing platform at 123 meters.
Nishijin is a neighborhood lying inland of Momochihama and is where Byeong-Hee Kim lives. Shunsuke Saruwatari, Banba, and Lin all visit his apartment building with intent to kill him, and Hironobu Shigematsu cleans up the crime scene.
PC Doctor's Studio
PC Doctor's Studio is a computer repair shop in Nishijin run by Siva. The front of the store is a normal maintenance shop, while the back room houses Siva's personal work space from which he operates as a hacker and a hitman. It also serves as the meeting space for Siva, Irasawa, and Chegar, the .mmm operatives in Fukuoka.
Locations within Chuo Ward
Chuo is the smallest and densest ward within Fukuoka. It sits between Hakata and Sawara Ward in the city center. Numerous locations within Chuo's borders are visited and named throughout the series.
Saeki's Cosmetic Surgery Clinic
Saeki's Cosmetic Surgery Clinic is owned and run by Shinichi Saeki, a member of the Hakata Tonkotsu Ramens grasslot baseball team and a cleaner after hours. His clinic is often visited by other members of the team needing their wounds dressed, cosmetic surgery performed, or looking to buy corpses or body parts.
The Nagatani Dam is a freshwater dam a distance from Fukuoka's city center. The area around the dam is considered off-roading, and its seclusion is likely why it is chosen by Munakata as the place to blow up Jun Murase, Tatsuya Yamashiro, and Masaki Yoshida. Their deaths are treated as a traffic accident.
Watanabe Street is a long six-lane road with a grassy median on which Saeki's Cosmetic Surgery Clinic is situated. In the Niwaka Samurai Impersonator arc, Abe and Yamamoto are driving down this road when Yamamoto drives between two lines of traffic waiting at a red light, an incident that causes the avengers to target them later in the story.
Hirao is a neighborhood in Chuo Ward. In the second story arc, a group of yakuza is headquartered in an otherwise empty five-story building when Abe and Yamamoto take on a job to shoot the members of the group, leaving one witness.
Featured on the cover of the third light novel, Ohori Park (大濠公園, Ōhori-kōen, lit. large moat) includes a narrow island within a lake encircled by a paved running path. It is registered as a place of scenic beauty in Japan and is situated near the Fukuoka Castle ruins, city museums, and baseball stadium. The city has a large fireworks display in the park in early August, which Zenji Banba gets excited for but regretfully misses. In the Shou Wang arc, Naoya Nitta and Tony Lau meet in the park on two occasions and rent a swan boat to paddle around the lake, where they are able to discuss business without being overheard.
Locations within Tenjin
Tenjin is the downtown area of Fukuoka, the city's main shopping district and administrative center and a district within Chuo Ward.
Kego Park is a small concrete park in Tenjin nestled between the shopping area and the intercity transportation terminals. In the series' first story arc, Mayor Harada is giving a speech in Kego Park when Banba pops a child's balloon to gauge Reiko Asakura's reaction to the noise.
Mitsukoshi Lion Plaza
The plaza, located near Kego Park, contains two large lion statues, one of which is pictured on the cover of the series' gaiden anthology. In the Mayor Harada Scandal Arc, Banba meets the mayor's hitmen Munakata and Shinohara here while posing as a member of the mafia, and he gives them Lin in a suitcase.
Suzaki City (sometimes romanized as Susaki City) is a neighborhood in Tenjin near Hakata Bay where the Kakyuu Association houses its offices and torture rooms. The final fights of the first, second, and third light novel volumes all take place in Suzaki City.