shì​wèi​zhī​jǐ​zhě​sǐ, nǚ​wèi​yuè​jǐ​zhě​róng

reciprocal devotion

士为知己者死,女为悦己者容 (士為知己者死,女為悅己者容) shì​wèi​zhī​jǐ​zhě​sǐ, nǚ​wèi​yuè​jǐ​zhě​róng
reciprocal devotion
a true gentleman will sacrifice his life for a friend who understands him, as a woman makes herself beautiful for her sweetheart

Sources

Definitions
CC-CEDICT