While of course we can clearly label Don Juan as a charlatan without morals of any kind, it is in some way a charming quality. Even while we are scandalized, we can’t help but be intrigued by the antics of a perfect rogue. This is especially true when his misadventures fall upon themselves in such comical ways, like when assuring both Charlotte and Mathurine of his undying affection and loyalty, at the same time. Even Sganarelle’s exasperated attempts to lead Don Juan to the path of morality seem lighthearted.
It seems to me that we only truly realize how devious Don Juan is when he decides to live the life of a hypocrite: accusing everyone else of impiety while flagrantly living in sin. As convoluted as it seems, previously to this decision Don Juan was almost noble in his conviction to live immorally. He truly believed, I feel, that it was his right to seduce every beautiful woman he saw. At the same time he also had a clear sense of what was right and wrong, even if he chose only sometimes to act on them, like when he helped Don Carlo when he was outnumbered. Don Juan may have lived by his own rules, but at least it meant that he chose to do good of his own volition, not because he was taught to do so in the name of some higher being. This is why it seems especially wrong when he chooses to live hypocritically, and it leads ultimately to his downfall.
