I actually love to read, and write about, virtuous men. If the "bad" in "bad boys" is "evil lite," (and not just rebellious or surly) I'm not at all interested, and I can't imagine how they could be conceived of as romance heroes.
I've read blurbs for romance novels with heroes who are demons. My gosh, demons are about causing pain, injury and destruction for humans. That is their whole purpose. They can't be redeemed by the love of a good woman or anything else. Of course, an author may choose to portray demons unrealistically, as having some redeeming qualities, but why? Evil exists -- all you have to do is look at the news headlines. All the fake sugar-coating in the world doesn't hide it. Why not just write a hero who is a good man with realistic flaws?
I like virtuous heroes (not flawless ones, as that doesn't exist) who are tough, sweet, loving men who take their responsibilities seriously -- men of principle, courage, and passion who do not let their passions master them. Give me heroes who are the flesh and blood sons of Adam struggling to live up to the nobility of human nature and harness their less noble components. Because, to me, good is soooo much sexier than evil.
Opinions do differ about what constitutes evil. The Dungeons and Dragons system for example has a grid of 9 alignments - are you limiting your heroes only to people who are "lawful good", the ones behind the stereotype "good is boring"?
Google image search: d&d alignment. You can find an image that corresponds to fiction you are familiar with and see which character is what:
https://www.google.com/search?q=d&d...HgsASsioK4CQ&ved=0CAgQ_AUoAQ&biw=1024&bih=674
Consider Robin Hood - he's clearly conceived as a romantic hero, but he is definitely a thief. He's not forced into theft like Aladdin, he could easily be earning a living as a mercenary archer. Robin Hood is also opposed to the local law enforcement and bureaucracy. So he's not aligned lawful. He actively enjoys causing chaos and partying, so he's no neutral either, but chaotic. Specifically he's an example of a chaotic good alignment.
Now consider Captain Jack Sparrow from the Pirates of the Caribbean movies. Lots of people have a crush on him, not just because he's played by Johnny Depp, but also because as a character he has a great sense of humor and also a great sense of theatricality. He represents whimsy and magic. So again, he's definitely not lawful, and past neutral to chaotic. But he's not good either. He's not motivated to go out of his way to avoid killing others, nor does he have compunctions against trying to seduce an engaged or married woman into a one night stand. His favorite hobby is drunken carousing. Can't really be described as virtuous. Morally, he's neutral. So he'd be an example of a chaotic neutral alignment character who is still considered a romantic hero. Han Solo from Star Wars is another example of a charmingly roguish chaotic neutral character.
Now for a futuristic example, let's look at Captain Picard from Star Trek. He's definitely interested in law and order. He's also a pragmatist, not an idealist; he was conceived as a strong contrast to Captain Kirk, who regularly breaks rules for the sake of his ideals. Captain Picard's alignment is Lawful Neutral. And again, his character is considered romantically attractive by many fans.
This one you might not be familiar with, but I strongly recommend that anyone who hasn't seen Dr. Horrible's Sing-Along Blog should do so immediately!
Dr. Horrible, like Picard, is very fond of law and order. But he sees all the problems with the world, like prejudice and bullying, and he comes to the conclusion that he really needs to take over the world to make sure it is ruled properly. He's completely honest, open, and sane about being a super villain (well, sane aside from the usual emotional trauma from having been the victim of bullying and unrequited love and such). He's likeable and trustworthy... and his alignment is lawful evil, the same as Darth Vader.
Even chaotic evil characters, at the total other corner of the grid from where we started, can be charismatic, charming, sexy, clever, stylish devils. The Joker from the Batman universe has had various incarnations; the one in the recent movies is too disturbing to be considered attractive in pretty much any way, but some of the older incarnations of him were funny, creative, sweet to his girlfriend, and out to cause chaos in the most entertaining way possible. Loki is another villain whose more humorous versions were chaotic evil (and he has SO MANY FANGIRLS). The Mask from the Jim Carrey movie of the same name is a third example of an appealing chaotic evil character.
(I skipped a few of the combinations, but I think the point is illustrated; it's really hard to define "evil" in such a way that no evil characters are attractive, appealing, or romantic.)