One day, executive Tonegawa Yukio was ordered by Hyoudou Kazutaka, the chairman of the Teiai Group, to plan a "game of death" for the debtors! What awaited Tonegawa, who immediately held a planning meeting, was suffering, agony, and despair! The diabolical spin-off, depicting Tonegawa's anguish between the chairman and the blacksuits, starts now!

Ichijou Seiya is a young prodigy who is the manager of the Teiai underground casino and the creator of the diabolical pachinko machine "The Bog." Before his fight to the death with his nemesis, Itou Kaiji, he had a smoldering youth and was unable to make anything of himself. The story is set in Ooyama, Itabashi, Tokyo, a "bog" that has swallowed up all the dreams, hopes, and despairs of young people, and is about the ambitions and difficulties of freelancer Ichijou and his younger colleague Murakami who move into the capital and live in a tiny apartment.

At a certain prison under the surface, the "bottom of the bottom" that is the Teiai Underground Labor Facility, there is a man who uses his "one-day outing passes" to go above ground and enjoy all the luxuries of life while living in the poor conditions of the underground. His name is Ootsuki, and he is the leader of Squad E and a master of enjoying himself all day long with eating, drinking, and having a great time.