Some companies are compelling their younger employees to work more than 100 hours of uncompensated overtime a month to maximize their profits.

Japan has been derided for its long working hours for decades, and the risks of the hazardous practice eventually led to the infamous term "karoshi," or death from overwork.

Thanks to the Great Recession, however, a new term is circulating among young workers to describe companies that depend on such exploitation: "burakku kigyo" (black company).