https://en.wikipedia.org/wiki/Black_company_(Japan)

A black company (ブラック企業/ブラック会社, burakku kigyō/burakku gaisha), also referred to in English as a black corporation or black business, is a Japanese term for a company that is exploitative or abusive towards its workers.

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While specifics may vary from workplace to workplace and company to company, a typical practice at a black company is to hire a large number of young employees and then force them to work large amounts of overtime without overtime pay. Conditions are poor, and workers are subjected to verbal abuse and “power harassment” (bullying) by their superiors. In order to make the employees stay, superiors of black companies would often threaten young employees with disrepute if they chose to quit.