古有照妖镜今有卸妆油
[gŭ yŏu zhào yāo jìng jīn yŏu xiè zhuāng yóu]
Ancient Chinese legends spoke of magic mirrors that revealed the true forms of demons and monsters (the Demon-Revealing Mirror). Here it compares this legendary item with modern-day makeup remover, indicating how people today need it not just to remove makeup but metaphorically to see 'true' faces.