Akagi is a young boy who is a very talented gambler and makes remarkable wins in the story. In the first story he starts to play mahjong against Japanese mafia (Yakuza) for the first time in his life, but learns the game quickly and wins. Mahjong is a game that involves huge amounts of money and the Yakuza gangs use it to earn money, so when Akagi first won, it was his first step into the underground business. Akagi shows incredible talent throughout the story, but he also is a heretic that makes him different from others - his playing style is characterized by extremely risky and far-reaching bluffing techniques, which excite and terrify experienced players, as does his cheating ability, which he uses rarely, but to great effect. In the end he becomes a legend in the underground world.
(taken and edited from Wikipedia)

Picture	Real Name	Description
	Shigeru Akagi	Having very narrowly survived a game of chicken, Akagi enters a mahjong parlor in hopes of getting a chance to dry off and rest. He stumbles in on Nangou, who is playing (and losing) a game where his life is on the line. Though he knows nothing about mahjong, Akagi gives some risky, but effective advice, allowing Nangou to win a round and narrowly avoid death. Nangou, sensing a power from the boy, describes the basic rules of the game and entrusts his game to Akagi. Being completely fearless, very manipulative and calculating, Akagi takes risks other high-ranked players are not capable of, and in short order not only wins his first match, but also moves up to even higher stakes games. With this talent for gambling, Akagi's rise as a mahjong legend is inevitable.