It can be pleasurable, delicious, or addictive, it can make you more badass, and it even makes you more sexy.
Even though Beauty Equals Goodness, some villains are just gorgeous.
Often a consequence of Power Is Sexy, since Mooks aren't that attractive. Both a cause of and a result of Jerkass Dissonance.
They hide their demonic soul behind the face of an angel.
This character's almost guaranteed to garner loads of entirely undeserved sympathy from fans, but is so ingrained in certain cultures that it's not going away any time soon.