Tobaku Datenroku Kaiji Kazuya-Hen Edit
He is first introduced in the series by being forced to pay his debt with his kidney. Here, Chang and Mario barge into the room and offer their kidneys in exchange for paying off his debt. Kazuya, being in the same room and witnessing this offers them to play in his game, the Salvation game, to pay off their debt.
Out of the three participating, he in the end fails to put his trust into his friends and bails out taking all the money for himself leaving Chang and Mario behind without looking back nor saying a word.
Tobaku Datenroku Kaiji: 24 Oku-hen Edit
He is last seen when Chang and Mario go back to their house to retrieve their passports. He offers each of them 1 millions Yen to compensate for abandoning them during the Salvation game. Disgusted, after retrieving their passports they throw the money right back at him and leave him behind.
As he is not aware of the fact that Kaiji, Chang and Mario won 2.4 billions Yen, he calls them as fools and informs the blacksuits to pursuit them.