Koichi Iwasaki (Oto Izaki), a moneylender, spends his days collecting money by ruthlessly chasing people. Yakuza has nothing to do with him!One day, he meets his benefactor Bamba (Yu Matsuda), who saved him from being an outlaw. Bamba continues to rack up his own debts instead of taking care of the young people. Koichi, who knows everything about black money, senses the danger and tries to save Bamba by giving him guidance. However, he learns that the person to whom he owed the debt is Kito (Kenko Kaneko), who taught Koichi the basics of black money.