He is a sexist 'pig'. = He is a 'male chauvinist pig'. [=he is a man who thinks women are not equal to men]
The train station will be renovated 'when pigs fly'. [=it will never be renovated]
“This time I think he'll ask me to marry him!” “Yeah, and 'pigs might fly'.”
(..) "In Echo's Pond, sights thee have seen. Choose to make them reality or dream." Veronique: Rick? You pig. - Josh: Rick, what the fuck? - Anton: He's no friend of mine. Erica: Rick, is there anybody in this room that has something nice (..)2009 The Black Waters of Echo's Pond