Princess Iron Fan is a popular character from the classic novel Journey to the West. She was1 the wife of the main antagonist, Bull-Demon King (牛魔王 niú mó wáng), and together they had a son called Red Boy (红孩儿 hóng hái ér).
1 They divorced after Princess Iron Fan discovered her husband had been having an affair with a fox-spirit called the Jade-Faced Fox (玉面狐狸 yù miàn hú lí).
She is a beautiful mountain goddess2 that resides in Ba Jiao Cave (芭蕉洞 bā jiāo dòng) on Cui Yun Mountain (翠云山 cuì yún shān), and wields the Ba Jiao Fan (芭蕉扇 bā jiāo shàn) - often referred to as the Banana Leaf Fan in English. The Banana Leaf Fan is a large magical fan with the ability to create whirlwinds that can put out any fire. In the novel, Princess Iron Fan uses her magical Banana Leaf Fan to put out the fires on Fire Mountain (火焰山 huǒ yàn shān) once every year. She chooses to do this annually (rather than permanantly) so that the local villagers worship her as a goddess and make offerings to her in return for their safety.
2 There is much deliberation regarding the nature of Princess Iron Fan. It is written that she has "attained the Way" (a higher level of attainment in Daoism) and that she is a Xian (仙 xiān) - often translated to "fairy" in English, although the terminology is misleading - but in the novel she clearly isn't "good," which leads a lot of critics to believe she is a Yao (妖 yāo) - often translated to as "monster" or "demon" in English, although once again, the terminology is misleading. Officially, however, she is a Xian.