From Bai Juyi's (
白居易) Tang-dynasty 《
琵琶行》 (Song of the Pipa). The once-famous courtesan narrates her decline: 『
门前冷落鞍马稀,
老大嫁作商人妇』— 'the gate grew cold, the horses few; grown old, I married a merchant.'
鞍马 ('saddle-horses') is metonymy for the well-off visitors who once crowded her door.