Found an article from Japan Times (non-paywall link) explaining that the bill is about Japanese immigration law adjusting at least in part the ability to deport asylum applications.
First four paragraphs of the article as a jumping off point:
Parliament on Friday passed a bill to revise an immigration and refugee law that will allow authorities to deport individuals who repeatedly apply for asylum, despite objections from some opposition parties.
The Upper House enacted the law with the support of the ruling Liberal Democratic Party, led by Prime Minister Fumio Kishida, and its junior coalition partner, Komeito, as well as other right-leaning opposition forces.
The previous law governing such matters did not allow officials to send a foreign national back to their home country while their application for refugee status was pending, and immigration authorities suspect many have abused the system by applying multiple times in order to remain in Japan.
Under the amended law, the government will aim to reduce long-term detention in immigration facilities and encourage the expulsion of foreign individuals who do not comply with deportation orders