Tomohiro Miyoshi (三好 智広) is a worker from Group E paying off his debts by working in the underground labor camp.
He is a member of the 45ers.
Tobaku Hakairoku Kaiji
He and several others form a group called the 45ers (people who earn 45,000 perica due to debt) and sacrifice to get out of debt and start earning their regular 92,000 perica help Kaiji defeat Ōtsuki.
Tobaku Datenroku Kaiji
After getting out of the underground labor camps, he and Maeda start working for Takashi Muraoka in his casino. They manage to convince Kaiji to gamble with the president by convincing him that they can help him cheat in the gamble. This gamble being the Mine Field Game “17 Steps”.
Unfortunately for Kaiji, it was the opposite situation; Muraoka managed to convince them that Kaiji must be hiding excess money that he won from the Bog due to the fact that they are ignorant about the massive loan Kaiji took from Endou and that the payout from the Bog was divided among the three who participated. This resulted in them helping Muraoka instead to cheat while gambling with Kaiji.
After Kaiji manages to figure out their betrayal, he beats them both up before finishing the gamble with Muraoka.
The misunderstanding between the three is never cleared up.
Tobaku Datenroku Kaiji: One Poker-hen
At the beginning of the arc he and Maeda are seen talking to Muraoka about the amount of money he lost to Kaiji.