The Nagasaki family consists of four people: the parents and twin siblings. That night, the three except for the father and Kajitsu were relaxing in the living room, while Kajitsu went to a brothel to commemorate the end of his life as an office worker. Exhausted by human relationships, Kajitsu wanted to build everything from scratch, so he decided to move to the countryside. Meanwhile, his wife Hiromi was having an affair with the mediocre actor Fuji Ikuma, but she broke up with him, thinking it was a good opportunity to have the ideal affair. Hiromi is what the world calls a beautiful witch. She thought there must be someone more suitable for her than a man like Ikuma.

Year 201X. Japan has achieved economic revitalization due to the legalization of betting authorized by the government due to the enforcement of the betting regulations. A gambling vocational school (commonly known as Tobasen) was established to train specialists so that they can compete with other countries even in gambling. Only the gambling arm can climb. Meanwhile, Mizuho and four female students are gathered in the classroom. They were some of the most problematic children in Tobasen. Then, the teacher tells me the startling test contents. If he wins, he will graduate as a gambling specialist. However, if he lost, he was stripped of all his clothes, and he was a mahjong undressing, breaking the rules that death sanctions were waiting.