Monmon is a stray monkey who travels with his younger brother Monchak, committing thefts along the way. One day, he falls protecting his brother from a hunter and is sent to a hellish monkey prison! Monmon's life in prison begins, surrounded by delinquent monkeys that would silence crying children, including Big John the cheerleading monkey and Watchy the biker monkey! Tsunomaru-sensei's hilarious debut work is here!