https://www.history.com/articles/comfort-women-japan-military-brothels-korea

Prior to and during World War II, the Japanese Imperial Army institutionalized a system of military sexual slavery. An estimated 200,000 women and girls—a significant portion of whom were Korean—were abducted, deceived, and forced into brothels. They were subjected to daily rapes and brutal physical abuse. The long-lasting impacts of these atrocities have remained a highly contested diplomatic issue between South Korea and Japan, with survivors demanding formal apologies and reparations.

(https://xoxohth.com/thread.php?thread_id=5891241&forum_id=2#50056857)