@wolfwood:
http://www.onemanga.com/One_Piece/499/13/
He fucking shoots her fiance just so that he can kidnap that woman from the streets, take her back to his palace and rape her until he's tired of it and then throw her out like yesterdays garbage. Everything else that has happend pales when compared to this.
I would agree that was definately the most evil act i've seen. But he was pretty much raised to believe that everyone is beneath him, and he can get what he wants with no one to stand in his way.
Might have to go with Enel. He destroyed his home island as a display of his power… Then went on to ruthlessly dictate over Skypiea, taking slaves to work on the Maxim and then before departing, attempting to destroy Skypiea. I doubt he was raised to believe he was a god, so he must have come to that foolish conclusion, and what he did was pure evil, chosing between who lives and dies, and in the end, deciding they should all die.