Whats wrong with rape/incest?

I'm cool with it when it's drawn on photoshop or sketched onto paper. lead, ink and pixels don't have real feelings. As long as the reader doesn't go off trying that stuff in real life, it's all good to keep it locked up in fantasy land.

They're fictional characters. And I believe there's nothing wrong with fiction...

I watched something like that once. Although I'm a fan of both incest and rape separately in hentai, it made me cringe watching it. There's something about raping a sister that just seems wrong.

I don't see any problems with either, so long as the former stays fictional. So long as it isn't forced upon me and has fans that try and shove it down my throat, I'm indifferent to the matter. Although I'm fond of incest for some reason.

In fiction, everything is fine, as long it is tagged properly so that I don't read something which I don't want ;-)
Everyone got their own preferences, what's wrong with that? Just keep in mind that fiction is fiction, reality is reality. If someone doesn't know that, it's his fault and not fault of the fiction.

About rape and incest in RL:
Rape is of course wrong, since doing something against someone's will is always wrong.
But about Incest, imho there's nothing wrong about that. If it's mutual love between two human, why not. It's the same concept behind tolerating gay people. Just be sure not to have kids.
Of course I can understand if still many think of incest to be wrong for yourself, but that doesn't mean you must prohibit it for others, right?