素面朝天

Etymology
Originally used in reference to Lady of the State of Guo, the sister (or cousin) of (the renowned beautiful consort of the ). Per the Unofficial Biography of Yang Guifei (《楊太真外傳》) by :

Idiom

 * 1)  to present oneself to the emperor without any makeup
 * 2)  to wear no makeup; to show one's natural features; to present oneself just as one is