Violet was Doflamingo’s bae?

Q: Why do Doflamingo and Violet call each other “Doffy” and “Viola”?

Oda: Actually there is a profound setting about it, but I’m afraid I can’t tell you. I told my editor about it, though. Considering ONE PIECE is Shonen manga, I’d like to hide it since the reason is for adult audience. Dressrosa is a nation of passion, indeed!!