Kakiuchi City (垣内市, Kakiuchi-shi) is a fictional city located in the Aichi prefecture and the residence of Natsumi Kimiyoshi and her family after they move there from Okinomiya due to her father's transfer. While it is not named in the original Onisarashi-hen manga, it is given a name in the visual novel adaptation Someutsushi-hen It is also the residence of Detective Tomoe Minai after she is transferred there from Ibaraki. Kakiuchi City serves as the main setting of Onisarashi-hen, Someutsushi-hen and Kageboushi-hen.
Kakiuchi City is described as a commuter town adjacent to the metropolitan area in the Chubu region of Japan, with shopping centers, movie theaters and other modern facilities that Okinomiya does not offer. It is blessed with a robust transportation network, including an airport and was famous in the 1980s for its dramatic population rise at the time. Saeki Hospital, owned by Chisato Saeki's family is another notable location in which many important events take place.
Kakiuchi is also Tomoe's jurisdiction. She investigates the incidents perpetrated by the former residents of Hinamizawa who show erratic behavior after the Great Hinamizawa Disaster. Detective Kuraudo Ooishi and Mamoru Akasaka also try to find out the truth behind the gas disaster by investigating the incidents in Kakiuchi City.