Kemono no Zokusei is an adventure game based on the anime series Cyber City Oedo 808 by Yoshiaki Kawajiri. The events of the anime and the game are set in 2808. Computerized crime has become rampant, and police has restored an ancient Japanese feudal habit of hiring particularly dangerous convicts to hunt down criminals. The player takes control of one of such convicts, Shunsuke Sengoku, the main protagonist of the anime. He must find his companions, the blind ex-boxer and hacker Gogol, and the effeminate Benten, in order to complete an assignment given to him by the police and eventually lower his sentence in prison.
The game contains first-person screens with typical Japanese-style menu-based verb-object interaction during dialogues; however, most of the exploration in the game is done in third person, as Sengoku explores top-down areas, talking to people and gathering information and clues. There are no real puzzles in the game, but in some situations inventory items can be used or shown to characters.