Black Joke (ブラック・ジョーク, Burakku Jōku) is a manga series written Rintarou Koike and illustrated by Masayuki Taguchi.
Black Joke was serialized from Issue 2008-5 to Issue 2011-7 of Young Champion, though being published in biweekly magazine (published once every two weeks), the manga was published as a monthly series. The manga was moved to the monthly magazine Young Champion Retsu and continued in May 2011 from Issue 2011-6, where is still being published.
Japan is now the 51st state of the U.S.A.. The isle of Neon, located near Japan, is the only place where prostitution and gambling are legal. There, Italian Mafia, Chinese Triad and Yakuza fight each other to gain the control of casinos and brothels.