There is a tradition of clearly erotic literature, which is less known. It is supposed that most such works have been purged in the periodic book burnings that have been a feature of Chinese history. However, isolated manuscripts have survived. Chief among these is the anthology "Bian er chai" (), a series of four short stories in five chapters each, of passion and seduction. The first short story, "Chronicle of a Loyal Love", involves a twenty-year-old academician chasing a fifteen-year-old scholar and a bevy of adolescent valets. In another, "Qing Xia Ji" (), the protagonist, Zhang, a valiant soldier with two warrior wives, is seduced by his younger friend Zhong, a remarkable arrangement as it is stereotypically the older man who takes the initiative with a boy. The work appeared in a single edition some time between 1630 and 1640.