A Japanese man who says he was penalised for taking paternity leave brought his case to a Tokyo court on Thursday, a rare suit in a country struggling with one of the world's lowest birthrates.
The 38-year-old, who has remained anonymous, is suing his employer, sportswear maker Asics for 4.4 million yen ($41,000) in damages.
He claims that after he took paternity leave, he was transferred to jobs that bore no relation to his skills or experience.
By law, Japan offers comparatively generous parental leave - both parents can take up to a year off, with additional renewable six-month periods if a nursery place is unavailable.
But while more than 80 percent of women take parental leave, only six percent of fathers do. The disparity, activists say, is partly due to pressure from employers and a society that prizes long work hours.
The plaintiff took a year's leave in 2015-2016 when his first child was born, and another year in 2018-2019 after the birth of his second child.
He has accused Asics of effectively punishing him for his decision and doing so as a warning to other employees who might want to take time off.
Of the small number of men in Japan who take paternity leave, more than 70 percent are away for less than a fortnight.
Fathers face harsh criticism for taking leave, despite being legally entitled to do so as the government tries desperately to boost the birthrate, the man's lawyer Naoto Sasayama told AFP.
"The culture established in a post-war Japan expects men to be the sole breadwinner. Stay-at-home men are considered extremely strange," he said.
"That idea is no longer accepted but some people still can't understand it," he said.
Parental leave is not paid for by employers, but government subsidies are available.