Lovers’ language, give me an exact and poetic comparison to say what those eyes of Capitu were like. No image comes to mind that doesn’t offend against the rules of good style, to say what they were and what they did to me. Undertow eyes? Why not? Undertow. That’s the notion that the new expression put in my head. They held some kind of mysterious, active fluid, a force that dragged one in, like the undertow of a wave retreating from the shore on stormy days. So as not to be dragged in, I held onto anything around them, her ears, her arms, her hair spread about her shoulders; but as soon as I returned to the pupils of her eyes again, the wave emerging from them grew towards me, deep and dark, threatening to envelop me, draw me in and swallow me up.
―Machado de Assis, Dom Casmurro