Kozai got hooked on tranquillizers to deal with the anxiety and she was isolated after the agency convinced her to cut off contact with family to focus on her career.
Japan releases some 30,000 adult films annually, according to industry figures.
But like Kozai and others, she succumbed to the pressure.
For Kozai, who is mulling legal action against her former agency, the arrests and heavy media coverage may be the tipping point for change -- and help other women avoid her fate.
Young women who have dreamt of an acting career quickly sign contracts.
A new police crackdown will closely monitor agents hunting women on the street, but Human Rights Now lawyer Kazuko Ito told The Guardian the entertainment industry has to change.
Kozai eventually left the agency that she says brainwashed her.
And it can be nearly impossible to get coerced pornography out of distribution in the internet age.
Description: She was later given a contract that stated the modelling job would require her to be nude.