From the back of the box:
19XX, in the heart of a large city, five criminal gangs live side by side, where the only thing that really counts is to gain power. The main character in the story is Asuka Kyou. One day he gets drawn into a fight as he is helping a girl. During the struggle, he is noticed by a powerful man, a boss of one of the largest gangs linked to the Alliance. With his recommendation, Kyou starts the rise to power within his new "family". But then the boss of the Alliance is attacked from within the organisation, and this is a clever trap to destroy the Alliance.