This classic theme – “Leda and the Swan” – is originating in greek mythology (sometimes I ask myself, what isn´t;), and has also been a very popular motif in the Renaissance.
In short: Zeus is succesfully seducing Leda (who, among others, is the mother of Helen – you know, that absolutely beautiful girl who apparently drove all the men crazy and thus led to the Troian War in consequence) in the guise of a swan. There are a lot of drawings and paintings that depict this scene rather to the point, as did one of the greatest painter in history, the famous Michelangelo (click here, if you want to have a quick look! https://en.wikipedia.org/wiki/Leda_%28mythology%29#/media/File:Leda_-_after_Michelangelo_Buonarroti.jpg. ) I, however, approached the theme somewhat more restrained;)