Living with his brother and sister-in-law, Makoto is home alone when a stranger breaks in, threatening Sayuri with a knife and assaulting her. Helpless and tied up, Makoto is forced to watch as the man reveals he's an ex-boyfriend seeking revenge for being dumped. Makoto is then violently dragged into the assault, and as more men join—including a friend—the gangbang escalates to a 5P. Sayuri's resistance gradually fades as she succumbs to pleasure.