Aki is a city located in Kōchi Prefecture, Japan. As of 31 July 2022, the city had an estimated population of 16,370 in 8076 households and a pop…Aki is a city located in Kōchi Prefecture, Japan. As of 31 July 2022, the city had an estimated population of 16,370 in 8076 households and a population density of 52 persons per km². The total area of the city is 317.21 square kilometres.